find(1)
NAME
find - search for files in a directory hierarchy
SYNOPSIS
find [-H] [-L] [-P] [-D debugopts] [-Olevel] [starting-point...] [expression]
DESCRIPTION
This manual page documents the GNU version of find. GNU find searches the directory tree rooted at each given starting-point by evaluating the given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is false for and operations, true for or), at which point find moves on to the next file name. If no starting-point is specified, `.' is assumed. If you are using find in an environment where security is important (for example if you are using it to search directories that are writable by other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding Files and comes with findutils. That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of information.
OPTIONS
The -H, -L and -P options control the treatment of symbolic links.
Command-line arguments following these are taken to be names of files
or directories to be examined, up to the first argument that begins
with `-', or the argument `(' or `!'. That argument and any following
arguments are taken to be the expression describing what is to be
searched for. If no paths are given, the current directory is used.
If no expression is given, the expression -print is used (but you
should probably consider using -print0 instead, anyway).
This manual page talks about `options' within the expression list.
These options control the behaviour of find but are specified
immediately after the last path name. The five `real' options -H, -L,
-P, -D and -O must appear before the first path name, if at all. A
double dash -- can also be used to signal that any remaining arguments
are not options (though ensuring that all start points begin with
either `./' or `/' is generally safer if you use wildcards in the list
of start points).
-P Never follow symbolic links. This is the default behaviour.
When find examines or prints information a file, and the file is
a symbolic link, the information used shall be taken from the
properties of the symbolic link itself.
-L Follow symbolic links. When find examines or prints information
about files, the information used shall be taken from the
properties of the file to which the link points, not from the
link itself (unless it is a broken symbolic link or find is
unable to examine the file to which the link points). Use of
this option implies -noleaf. If you later use the -P option,
-noleaf will still be in effect. If -L is in effect and find
discovers a symbolic link to a subdirectory during its search,
the subdirectory pointed to by the symbolic link will be
searched.
When the -L option is in effect, the -type predicate will always
match against the type of the file that a symbolic link points
to rather than the link itself (unless the symbolic link is
broken). Actions that can cause symbolic links to become broken
while find is executing (for example -delete) can give rise to
confusing behaviour. Using -L causes the -lname and -ilname
predicates always to return false.
-H Do not follow symbolic links, except while processing the
command line arguments. When find examines or prints
information about files, the information used shall be taken
from the properties of the symbolic link itself. The only
exception to this behaviour is when a file specified on the
command line is a symbolic link, and the link can be resolved.
For that situation, the information used is taken from whatever
the link points to (that is, the link is followed). The
information about the link itself is used as a fallback if the
file pointed to by the symbolic link cannot be examined. If -H
is in effect and one of the paths specified on the command line
is a symbolic link to a directory, the contents of that
directory will be examined (though of course -maxdepth 0 would
prevent this).
If more than one of -H, -L and -P is specified, each overrides the
others; the last one appearing on the command line takes effect. Since
it is the default, the -P option should be considered to be in effect
unless either -H or -L is specified.
GNU find frequently stats files during the processing of the command
line itself, before any searching has begun. These options also affect
how those arguments are processed. Specifically, there are a number of
tests that compare files listed on the command line against a file we
are currently considering. In each case, the file specified on the
command line will have been examined and some of its properties will
have been saved. If the named file is in fact a symbolic link, and the
-P option is in effect (or if neither -H nor -L were specified), the
information used for the comparison will be taken from the properties
of the symbolic link. Otherwise, it will be taken from the properties
of the file the link points to. If find cannot follow the link (for
example because it has insufficient privileges or the link points to a
nonexistent file) the properties of the link itself will be used.
When the -H or -L options are in effect, any symbolic links listed as
the argument of -newer will be dereferenced, and the timestamp will be
taken from the file to which the symbolic link points. The same
consideration applies to -newerXY, -anewer and -cnewer.
The -follow option has a similar effect to -L, though it takes effect
at the point where it appears (that is, if -L is not used but -follow
is, any symbolic links appearing after -follow on the command line will
be dereferenced, and those before it will not).
-D debugopts
Print diagnostic information; this can be helpful to diagnose
problems with why find is not doing what you want. The list of
debug options should be comma separated. Compatibility of the
debug options is not guaranteed between releases of findutils.
For a complete list of valid debug options, see the output of
find -D help. Valid debug options include
exec Show diagnostic information relating to -exec, -execdir,
-ok and -okdir
help Explain the debugging options.
opt Prints diagnostic information relating to the
optimisation of the expression tree; see the -O option.
rates Prints a summary indicating how often each predicate
succeeded or failed.
search Navigate the directory tree verbosely.
stat Print messages as files are examined with the stat and
lstat system calls. The find program tries to minimise
such calls.
tree Show the expression tree in its original and optimised
form.
-Olevel
Enables query optimisation. The find program reorders tests to
speed up execution while preserving the overall effect; that is,
predicates with side effects are not reordered relative to each
other. The optimisations performed at each optimisation level
are as follows.
0 Equivalent to optimisation level 1.
1 This is the default optimisation level and corresponds to
the traditional behaviour. Expressions are reordered so
that tests based only on the names of files (for example
-name and -regex) are performed first.
2 Any -type or -xtype tests are performed after any tests
based only on the names of files, but before any tests
that require information from the inode. On many modern
versions of Unix, file types are returned by readdir()
and so these predicates are faster to evaluate than
predicates which need to stat the file first. If you use
the -fstype FOO predicate and specify a filesystem type
FOO which is not known (that is, present in `/etc/mtab')
at the time find starts, that predicate is equivalent to
-false.
3 At this optimisation level, the full cost-based query
optimiser is enabled. The order of tests is modified so
that cheap (i.e. fast) tests are performed first and more
expensive ones are performed later, if necessary. Within
each cost band, predicates are evaluated earlier or later
according to whether they are likely to succeed or not.
For -o, predicates which are likely to succeed are
evaluated earlier, and for -a, predicates which are
likely to fail are evaluated earlier.
The cost-based optimiser has a fixed idea of how likely any
given test is to succeed. In some cases the probability takes
account of the specific nature of the test (for example, -type f
is assumed to be more likely to succeed than -type c). The
cost-based optimiser is currently being evaluated. If it does
not actually improve the performance of find, it will be removed
again. Conversely, optimisations that prove to be reliable,
robust and effective may be enabled at lower optimisation levels
over time. However, the default behaviour (i.e. optimisation
level 1) will not be changed in the 4.3.x release series. The
findutils test suite runs all the tests on find at each
optimisation level and ensures that the result is the same.
EXPRESSION
The part of the command line after the list of starting points is the
expression. This is a kind of query specification describing how we
match files and what we do with the files that were matched. An
expression is composed of a sequence of things:
Tests Tests return a true or false value, usually on the basis of some
property of a file we are considering. The -empty test for
example is true only when the current file is empty.
Actions
Actions have side effects (such as printing something on the
standard output) and return either true or false, usually based
on whether or not they are successful. The -print action for
example prints the name of the current file on the standard
output.
Global options
Global options affect the operation of tests and actions
specified on any part of the command line. Global options
always return true. The -depth option for example makes find
traverse the file system in a depth-first order.
Positional options
Positional options affect only tests or actions which follow
them. Positional options always return true. The -regextype
option for example is positional, specifying the regular
expression dialect for regular expressions occurring later on
the command line.
Operators
Operators join together the other items within the expression.
They include for example -o (meaning logical OR) and -a (meaning
logical AND). Where an operator is missing, -a is assumed.
If the whole expression contains no actions other than -prune or
-print, -print is performed on all files for which the whole expression
is true.
The -delete action also acts like an option (since it implies -depth).
POSITIONAL OPTIONS
Positional options always return true. They affect only tests
occurring later on the command line.
-daystart
Measure times (for -amin, -atime, -cmin, -ctime, -mmin, and
-mtime) from the beginning of today rather than from 24 hours
ago. This option only affects tests which appear later on the
command line.
-follow
Deprecated; use the -L option instead. Dereference symbolic
links. Implies -noleaf. The -follow option affects only those
tests which appear after it on the command line. Unless the -H
or -L option has been specified, the position of the -follow
option changes the behaviour of the -newer predicate; any files
listed as the argument of -newer will be dereferenced if they
are symbolic links. The same consideration applies to -newerXY,
-anewer and -cnewer. Similarly, the -type predicate will always
match against the type of the file that a symbolic link points
to rather than the link itself. Using -follow causes the -lname
and -ilname predicates always to return false.
-regextype type
Changes the regular expression syntax understood by -regex and
-iregex tests which occur later on the command line. To see
which regular expression types are known, use -regextype help.
The Texinfo documentation (see SEE ALSO) explains the meaning of
and differences between the various types of regular expression.
-warn, -nowarn
Turn warning messages on or off. These warnings apply only to
the command line usage, not to any conditions that find might
encounter when it searches directories. The default behaviour
corresponds to -warn if standard input is a tty, and to -nowarn
otherwise. If a warning message relating to command-line usage
is produced, the exit status of find is not affected. If the
POSIXLY_CORRECT environment variable is set, and -warn is also
used, it is not specified which, if any, warnings will be
active.
GLOBAL OPTIONS
Global options always return true. Global options take effect even for
tests which occur earlier on the command line. To prevent confusion,
global options should specified on the command-line after the list of
start points, just before the first test, positional option or action.
If you specify a global option in some other place, find will issue a
warning message explaining that this can be confusing.
The global options occur after the list of start points, and so are not
the same kind of option as -L, for example.
-d A synonym for -depth, for compatibility with FreeBSD, NetBSD,
MacOS X and OpenBSD.
-depth Process each directory's contents before the directory itself.
The -delete action also implies -depth.
-help, --help
Print a summary of the command-line usage of find and exit.
-ignore_readdir_race
Normally, find will emit an error message when it fails to stat
a file. If you give this option and a file is deleted between
the time find reads the name of the file from the directory and
the time it tries to stat the file, no error message will be
issued. This also applies to files or directories whose names
are given on the command line. This option takes effect at the
time the command line is read, which means that you cannot
search one part of the filesystem with this option on and part
of it with this option off (if you need to do that, you will
need to issue two find commands instead, one with the option and
one without it).
-maxdepth levels
Descend at most levels (a non-negative integer) levels of
directories below the starting-points. -maxdepth 0
means only apply the tests and actions to the starting-points
themselves.
-mindepth levels
Do not apply any tests or actions at levels less than levels (a
non-negative integer). -mindepth 1 means process all files
except the starting-points.
-mount Don't descend directories on other filesystems. An alternate
name for -xdev, for compatibility with some other versions of
find.
-noignore_readdir_race
Turns off the effect of -ignore_readdir_race.
-noleaf
Do not optimize by assuming that directories contain 2 fewer
subdirectories than their hard link count. This option is
needed when searching filesystems that do not follow the Unix
directory-link convention, such as CD-ROM or MS-DOS filesystems
or AFS volume mount points. Each directory on a normal Unix
filesystem has at least 2 hard links: its name and its `.'
entry. Additionally, its subdirectories (if any) each have a
`..' entry linked to that directory. When find is examining a
directory, after it has statted 2 fewer subdirectories than the
directory's link count, it knows that the rest of the entries in
the directory are non-directories (`leaf' files in the directory
tree). If only the files' names need to be examined, there is
no need to stat them; this gives a significant increase in
search speed.
-version, --version
Print the find version number and exit.
-xdev Don't descend directories on other filesystems.
TESTS
Some tests, for example -newerXY and -samefile, allow comparison
between the file currently being examined and some reference file
specified on the command line. When these tests are used, the
interpretation of the reference file is determined by the options -H,
-L and -P and any previous -follow, but the reference file is only
examined once, at the time the command line is parsed. If the
reference file cannot be examined (for example, the stat(2) system call
fails for it), an error message is issued, and find exits with a
nonzero status.
Numeric arguments can be specified as
+n for greater than n,
-n for less than n,
n for exactly n.
-amin n
File was last accessed n minutes ago.
-anewer file
File was last accessed more recently than file was modified. If
file is a symbolic link and the -H option or the -L option is in
effect, the access time of the file it points to is always used.
-atime n
File was last accessed n*24 hours ago. When find figures out
how many 24-hour periods ago the file was last accessed, any
fractional part is ignored, so to match -atime +1, a file has to
have been accessed at least two days ago.
-cmin n
File's status was last changed n minutes ago.
-cnewer file
File's status was last changed more recently than file was
modified. If file is a symbolic link and the -H option or the
-L option is in effect, the status-change time of the file it
points to is always used.
-ctime n
File's status was last changed n*24 hours ago. See the comments
for -atime to understand how rounding affects the interpretation
of file status change times.
-empty File is empty and is either a regular file or a directory.
-executable
Matches files which are executable and directories which are
searchable (in a file name resolution sense). This takes into
account access control lists and other permissions artefacts
which the -perm test ignores. This test makes use of the
access(2) system call, and so can be fooled by NFS servers which
do UID mapping (or root-squashing), since many systems implement
access(2) in the client's kernel and so cannot make use of the
UID mapping information held on the server. Because this test
is based only on the result of the access(2) system call, there
is no guarantee that a file for which this test succeeds can
actually be executed.
-false Always false.
-fstype type
File is on a filesystem of type type. The valid filesystem
types vary among different versions of Unix; an incomplete list
of filesystem types that are accepted on some version of Unix or
another is: ufs, 4.2, 4.3, nfs, tmp, mfs, S51K, S52K. You can
use -printf with the %F directive to see the types of your
filesystems.
-gid n File's numeric group ID is n.
-group gname
File belongs to group gname (numeric group ID allowed).
-ilname pattern
Like -lname, but the match is case insensitive. If the -L
option or the -follow option is in effect, this test returns
false unless the symbolic link is broken.
-iname pattern
Like -name, but the match is case insensitive. For example, the
patterns `fo*' and `F??' match the file names `Foo', `FOO',
`foo', `fOo', etc. The pattern `*foo*` will also match a file
called '.foobar'.
-inum n
File has inode number n. It is normally easier to use the
-samefile test instead.
-ipath pattern
Like -path. but the match is case insensitive.
-iregex pattern
Like -regex, but the match is case insensitive.
-iwholename pattern
See -ipath. This alternative is less portable than -ipath.
-links n
File has n links.
-lname pattern
File is a symbolic link whose contents match shell pattern
pattern. The metacharacters do not treat `/' or `.' specially.
If the -L option or the -follow option is in effect, this test
returns false unless the symbolic link is broken.
-mmin n
File's data was last modified n minutes ago.
-mtime n
File's data was last modified n*24 hours ago. See the comments
for -atime to understand how rounding affects the interpretation
of file modification times.
-name pattern
Base of file name (the path with the leading directories
removed) matches shell pattern pattern. Because the leading
directories are removed, the file names considered for a match
with -name will never include a slash, so `-name a/b' will never
match anything (you probably need to use -path instead). A
warning is issued if you try to do this, unless the environment
variable POSIXLY_CORRECT is set. The metacharacters (`*', `?',
and `[]') match a `.' at the start of the base name (this is a
change in findutils-4.2.2; see section STANDARDS CONFORMANCE
below). To ignore a directory and the files under it, use
-prune; see an example in the description of -path. Braces are
not recognised as being special, despite the fact that some
shells including Bash imbue braces with a special meaning in
shell patterns. The filename matching is performed with the use
of the fnmatch(3) library function. Don't forget to enclose
the pattern in quotes in order to protect it from expansion by
the shell.
-newer file
File was modified more recently than file. If file is a
symbolic link and the -H option or the -L option is in effect,
the modification time of the file it points to is always used.
-newerXY reference
Succeeds if timestamp X of the file being considered is newer
than timestamp Y of the file reference. The letters X and Y
can be any of the following letters:
a The access time of the file reference
B The birth time of the file reference
c The inode status change time of reference
m The modification time of the file reference
t reference is interpreted directly as a time
Some combinations are invalid; for example, it is invalid for X
to be t. Some combinations are not implemented on all systems;
for example B is not supported on all systems. If an invalid or
unsupported combination of XY is specified, a fatal error
results. Time specifications are interpreted as for the
argument to the -d option of GNU date. If you try to use the
birth time of a reference file, and the birth time cannot be
determined, a fatal error message results. If you specify a
test which refers to the birth time of files being examined,
this test will fail for any files where the birth time is
unknown.
-nogroup
No group corresponds to file's numeric group ID.
-nouser
No user corresponds to file's numeric user ID.
-path pattern
File name matches shell pattern pattern. The metacharacters do
not treat `/' or `.' specially; so, for example,
find . -path "./sr*sc"
will print an entry for a directory called `./src/misc' (if one
exists). To ignore a whole directory tree, use -prune rather
than checking every file in the tree. For example, to skip the
directory `src/emacs' and all files and directories under it,
and print the names of the other files found, do something like
this:
find . -path ./src/emacs -prune -o -print
Note that the pattern match test applies to the whole file name,
starting from one of the start points named on the command line.
It would only make sense to use an absolute path name here if
the relevant start point is also an absolute path. This means
that this command will never match anything:
find bar -path /foo/bar/myfile -print
Find compares the -path argument with the concatenation of a
directory name and the base name of the file it's examining.
Since the concatenation will never end with a slash, -path
arguments ending in a slash will match nothing (except perhaps a
start point specified on the command line). The predicate -path
is also supported by HP-UX find and is part of the POSIX 2008
standard.
-perm mode
File's permission bits are exactly mode (octal or symbolic).
Since an exact match is required, if you want to use this form
for symbolic modes, you may have to specify a rather complex
mode string. For example `-perm g=w' will only match files
which have mode 0020 (that is, ones for which group write
permission is the only permission set). It is more likely that
you will want to use the `/' or `-' forms, for example `-perm
-g=w', which matches any file with group write permission. See
the EXAMPLES section for some illustrative examples.
-perm -mode
All of the permission bits mode are set for the file. Symbolic
modes are accepted in this form, and this is usually the way in
which you would want to use them. You must specify `u', `g' or
`o' if you use a symbolic mode. See the EXAMPLES section for
some illustrative examples.
-perm /mode
Any of the permission bits mode are set for the file. Symbolic
modes are accepted in this form. You must specify `u', `g' or
`o' if you use a symbolic mode. See the EXAMPLES section for
some illustrative examples. If no permission bits in mode are
set, this test matches any file (the idea here is to be
consistent with the behaviour of -perm -000).
-perm +mode
This is no longer supported (and has been deprecated since
2005). Use -perm /mode instead.
-readable
Matches files which are readable. This takes into account
access control lists and other permissions artefacts which the
-perm test ignores. This test makes use of the access(2) system
call, and so can be fooled by NFS servers which do UID mapping
(or root-squashing), since many systems implement access(2) in
the client's kernel and so cannot make use of the UID mapping
information held on the server.
-regex pattern
File name matches regular expression pattern. This is a match
on the whole path, not a search. For example, to match a file
named `./fubar3', you can use the regular expression `.*bar.' or
`.*b.*3', but not `f.*r3'. The regular expressions understood
by find are by default Emacs Regular Expressions, but this can
be changed with the -regextype option.
-samefile name
File refers to the same inode as name. When -L is in effect,
this can include symbolic links.
-size n[cwbkMG]
File uses n units of space, rounding up. The following suffixes
can be used:
`b' for 512-byte blocks (this is the default if no suffix is
used)
`c' for bytes
`w' for two-byte words
`k' for Kilobytes (units of 1024 bytes)
`M' for Megabytes (units of 1048576 bytes)
`G' for Gigabytes (units of 1073741824 bytes)
The size does not count indirect blocks, but it does count
blocks in sparse files that are not actually allocated. Bear in
mind that the `%k' and `%b' format specifiers of -printf handle
sparse files differently. The `b' suffix always denotes
512-byte blocks and never 1 Kilobyte blocks, which is different
to the behaviour of -ls.
The + and - prefixes signify greater than and less than, as
usual. Bear in mind that the size is rounded up to the next
unit. Therefore -size -1M is not equivalent to -size -1048576c.
The former only matches empty files, the latter matches files
from 1 to 1,048,575 bytes.
-true Always true.
-type c
File is of type c:
b block (buffered) special
c character (unbuffered) special
d directory
p named pipe (FIFO)
f regular file
l symbolic link; this is never true if the -L option or the
-follow option is in effect, unless the symbolic link is
broken. If you want to search for symbolic links when -L
is in effect, use -xtype.
s socket
D door (Solaris)
To search for more than one type at once, you can supply the
combined list of type letters separated by a comma `,' (GNU
extension).
-uid n File's numeric user ID is n.
-used n
File was last accessed n days after its status was last changed.
-user uname
File is owned by user uname (numeric user ID allowed).
-wholename pattern
See -path. This alternative is less portable than -path.
-writable
Matches files which are writable. This takes into account
access control lists and other permissions artefacts which the
-perm test ignores. This test makes use of the access(2) system
call, and so can be fooled by NFS servers which do UID mapping
(or root-squashing), since many systems implement access(2) in
the client's kernel and so cannot make use of the UID mapping
information held on the server.
-xtype c
The same as -type unless the file is a symbolic link. For
symbolic links: if the -H or -P option was specified, true if
the file is a link to a file of type c; if the -L option has
been given, true if c is `l'. In other words, for symbolic
links, -xtype checks the type of the file that -type does not
check.
-context pattern
(SELinux only) Security context of the file matches glob
pattern.
ACTIONS
-delete
Delete files; true if removal succeeded. If the removal failed,
an error message is issued. If -delete fails, find's exit
status will be nonzero (when it eventually exits). Use of
-delete automatically turns on the `-depth' option.
Warnings: Don't forget that the find command line is evaluated
as an expression, so putting -delete first will make find try to
delete everything below the starting points you specified. When
testing a find command line that you later intend to use with
-delete, you should explicitly specify -depth in order to avoid
later surprises. Because -delete implies -depth, you cannot
usefully use -prune and -delete together.
-exec command ;
Execute command; true if 0 status is returned. All following
arguments to find are taken to be arguments to the command until
an argument consisting of `;' is encountered. The string `{}'
is replaced by the current file name being processed everywhere
it occurs in the arguments to the command, not just in arguments
where it is alone, as in some versions of find. Both of these
constructions might need to be escaped (with a `\') or quoted to
protect them from expansion by the shell. See the EXAMPLES
section for examples of the use of the -exec option. The
specified command is run once for each matched file. The
command is executed in the starting directory. There are
unavoidable security problems surrounding use of the -exec
action; you should use the -execdir option instead.
-exec command {} +
This variant of the -exec action runs the specified command on
the selected files, but the command line is built by appending
each selected file name at the end; the total number of
invocations of the command will be much less than the number of
matched files. The command line is built in much the same way
that xargs builds its command lines. Only one instance of `{}'
is allowed within the command, and (when find is being invoked
from a shell) it should be quoted (for example, '{}') to protect
it from interpretation by shells. The command is executed in
the starting directory. If any invocation returns a non-zero
value as exit status, then find returns a non-zero exit status.
If find encounters an error, this can sometimes cause an
immediate exit, so some pending commands may not be run at all.
This variant of -exec always returns true.
-execdir command ;
-execdir command {} +
Like -exec, but the specified command is run from the
subdirectory containing the matched file, which is not normally
the directory in which you started find. As with -exec, the {}
should be quoted if find is being invoked from a shell. This a
much more secure method for invoking commands, as it avoids race
conditions during resolution of the paths to the matched files.
As with the -exec action, the `+' form of -execdir will build a
command line to process more than one matched file, but any
given invocation of command will only list files that exist in
the same subdirectory. If you use this option, you must ensure
that your $PATH environment variable does not reference `.';
otherwise, an attacker can run any commands they like by leaving
an appropriately-named file in a directory in which you will run
-execdir. The same applies to having entries in $PATH which are
empty or which are not absolute directory names. If any
invocation returns a non-zero value as exit status, then find
returns a non-zero exit status. If find encounters an error,
this can sometimes cause an immediate exit, so some pending
commands may not be run at all. The result of the action depends
on whether the + or the ; variant is being used; -execdir
command {} + always returns true, while -execdir command {} ;
returns true only if command returns 0.
-fls file
True; like -ls but write to file like -fprint. The output file
is always created, even if the predicate is never matched. See
the UNUSUAL FILENAMES section for information about how unusual
characters in filenames are handled.
-fprint file
True; print the full file name into file file. If file does not
exist when find is run, it is created; if it does exist, it is
truncated. The file names `/dev/stdout' and `/dev/stderr' are
handled specially; they refer to the standard output and
standard error output, respectively. The output file is always
created, even if the predicate is never matched. See the
UNUSUAL FILENAMES section for information about how unusual
characters in filenames are handled.
-fprint0 file
True; like -print0 but write to file like -fprint. The output
file is always created, even if the predicate is never matched.
See the UNUSUAL FILENAMES section for information about how
unusual characters in filenames are handled.
-fprintf file format
True; like -printf but write to file like -fprint. The output
file is always created, even if the predicate is never matched.
See the UNUSUAL FILENAMES section for information about how
unusual characters in filenames are handled.
-ls True; list current file in ls -dils format on standard output.
The block counts are of 1K blocks, unless the environment
variable POSIXLY_CORRECT is set, in which case 512-byte blocks
are used. See the UNUSUAL FILENAMES section for information
about how unusual characters in filenames are handled.
-ok command ;
Like -exec but ask the user first. If the user agrees, run the
command. Otherwise just return false. If the command is run,
its standard input is redirected from /dev/null.
The response to the prompt is matched against a pair of regular
expressions to determine if it is an affirmative or negative
response. This regular expression is obtained from the system
if the `POSIXLY_CORRECT' environment variable is set, or
otherwise from find's message translations. If the system has
no suitable definition, find's own definition will be used. In
either case, the interpretation of the regular expression itself
will be affected by the environment variables 'LC_CTYPE'
(character classes) and 'LC_COLLATE' (character ranges and
equivalence classes).
-okdir command ;
Like -execdir but ask the user first in the same way as for -ok.
If the user does not agree, just return false. If the command
is run, its standard input is redirected from /dev/null.
-print True; print the full file name on the standard output, followed
by a newline. If you are piping the output of find into
another program and there is the faintest possibility that the
files which you are searching for might contain a newline, then
you should seriously consider using the -print0 option instead
of -print. See the UNUSUAL FILENAMES section for information
about how unusual characters in filenames are handled.
-print0
True; print the full file name on the standard output, followed
by a null character (instead of the newline character that
-print uses). This allows file names that contain newlines or
other types of white space to be correctly interpreted by
programs that process the find output. This option corresponds
to the -0 option of xargs.
-printf format
True; print format on the standard output, interpreting `\'
escapes and `%' directives. Field widths and precisions can be
specified as with the `printf' C function. Please note that
many of the fields are printed as %s rather than %d, and this
may mean that flags don't work as you might expect. This also
means that the `-' flag does work (it forces fields to be left-
aligned). Unlike -print, -printf does not add a newline at the
end of the string. The escapes and directives are:
Alarm bell.
Backspace.
\c Stop printing from this format immediately and flush the
output.
\f Form feed.
\n Newline.
\r Carriage return.
\t Horizontal tab.
\v Vertical tab.
\0 ASCII NUL.
\\ A literal backslash (`\').
\NNN The character whose ASCII code is NNN (octal).
A `\' character followed by any other character is treated as an
ordinary character, so they both are printed.
%% A literal percent sign.
%a File's last access time in the format returned by the C
`ctime' function.
%Ak File's last access time in the format specified by k,
which is either `@' or a directive for the C `strftime'
function. The possible values for k are listed below;
some of them might not be available on all systems, due
to differences in `strftime' between systems.
@ seconds since Jan. 1, 1970, 00:00 GMT, with
fractional part.
Time fields:
H hour (00..23)
I hour (01..12)
k hour ( 0..23)
l hour ( 1..12)
M minute (00..59)
p locale's AM or PM
r time, 12-hour (hh:mm:ss [AP]M)
S Second (00.00 .. 61.00). There is a fractional
part.
T time, 24-hour (hh:mm:ss.xxxxxxxxxx)
+ Date and time, separated by `+', for example
`2004-04-28+22:22:05.0'. This is a GNU extension.
The time is given in the current timezone (which
may be affected by setting the TZ environment
variable). The seconds field includes a
fractional part.
X locale's time representation (H:M:S). The seconds
field includes a fractional part.
Z time zone (e.g., EDT), or nothing if no time zone
is determinable
Date fields:
a locale's abbreviated weekday name (Sun..Sat)
A locale's full weekday name, variable length
(Sunday..Saturday)
b locale's abbreviated month name (Jan..Dec)
B locale's full month name, variable length
(January..December)
c locale's date and time (Sat Nov 04 12:02:33 EST
1989). The format is the same as for ctime(3) and
so to preserve compatibility with that format,
there is no fractional part in the seconds field.
d day of month (01..31)
D date (mm/dd/yy)
h same as b
j day of year (001..366)
m month (01..12)
U week number of year with Sunday as first day of
week (00..53)
w day of week (0..6)
W week number of year with Monday as first day of
week (00..53)
x locale's date representation (mm/dd/yy)
y last two digits of year (00..99)
Y year (1970...)
%b The amount of disk space used for this file in 512-byte
blocks. Since disk space is allocated in multiples of
the filesystem block size this is usually greater than
%s/512, but it can also be smaller if the file is a
sparse file.
%c File's last status change time in the format returned by
the C `ctime' function.
%Ck File's last status change time in the format specified by
k, which is the same as for %A.
%d File's depth in the directory tree; 0 means the file is a
starting-point.
%D The device number on which the file exists (the st_dev
field of struct stat), in decimal.
%f File's name with any leading directories removed (only
the last element).
%F Type of the filesystem the file is on; this value can be
used for -fstype.
%g File's group name, or numeric group ID if the group has
no name.
%G File's numeric group ID.
%h Leading directories of file's name (all but the last
element). If the file name contains no slashes (since it
is in the current directory) the %h specifier expands to
`.'.
%H Starting-point under which file was found.
%i File's inode number (in decimal).
%k The amount of disk space used for this file in 1K blocks.
Since disk space is allocated in multiples of the
filesystem block size this is usually greater than
%s/1024, but it can also be smaller if the file is a
sparse file.
%l Object of symbolic link (empty string if file is not a
symbolic link).
%m File's permission bits (in octal). This option uses the
`traditional' numbers which most Unix implementations
use, but if your particular implementation uses an
unusual ordering of octal permissions bits, you will see
a difference between the actual value of the file's mode
and the output of %m. Normally you will want to have a
leading zero on this number, and to do this, you should
use the # flag (as in, for example, `%#m').
%M File's permissions (in symbolic form, as for ls). This
directive is supported in findutils 4.2.5 and later.
%n Number of hard links to file.
%p File's name.
%P File's name with the name of the starting-point under
which it was found removed.
%s File's size in bytes.
%S File's sparseness. This is calculated as
(BLOCKSIZE*st_blocks / st_size). The exact value you
will get for an ordinary file of a certain length is
system-dependent. However, normally sparse files will
have values less than 1.0, and files which use indirect
blocks may have a value which is greater than 1.0. The
value used for BLOCKSIZE is system-dependent, but is
usually 512 bytes. If the file size is zero, the value
printed is undefined. On systems which lack support for
st_blocks, a file's sparseness is assumed to be 1.0.
%t File's last modification time in the format returned by
the C `ctime' function.
%Tk File's last modification time in the format specified by
k, which is the same as for %A.
%u File's user name, or numeric user ID if the user has no
name.
%U File's numeric user ID.
%y File's type (like in ls -l), U=unknown type (shouldn't
happen)
%Y File's type (like %y), plus follow symlinks: L=loop,
N=nonexistent
%Z (SELinux only) file's security context.
%{ %[ %(
Reserved for future use.
A `%' character followed by any other character is discarded,
but the other character is printed (don't rely on this, as
further format characters may be introduced). A `%' at the end
of the format argument causes undefined behaviour since there is
no following character. In some locales, it may hide your door
keys, while in others it may remove the final page from the
novel you are reading.
The %m and %d directives support the # , 0 and + flags, but the
other directives do not, even if they print numbers. Numeric
directives that do not support these flags include G, U, b, D, k
and n. The `-' format flag is supported and changes the
alignment of a field from right-justified (which is the default)
to left-justified.
See the UNUSUAL FILENAMES section for information about how
unusual characters in filenames are handled.
-prune True; if the file is a directory, do not descend into it. If
-depth is given, false; no effect. Because -delete implies
-depth, you cannot usefully use -prune and -delete together.
-quit Exit immediately. No child processes will be left running, but
no more paths specified on the command line will be processed.
For example, find /tmp/foo /tmp/bar -print -quit will print only
/tmp/foo. Any command lines which have been built up with
-execdir ... {} + will be invoked before find exits. The exit
status may or may not be zero, depending on whether an error has
already occurred.
OPERATORS
Listed in order of decreasing precedence:
( expr )
Force precedence. Since parentheses are special to the shell,
you will normally need to quote them. Many of the examples in
this manual page use backslashes for this purpose: `\(...\)'
instead of `(...)'.
! expr True if expr is false. This character will also usually need
protection from interpretation by the shell.
-not expr
Same as ! expr, but not POSIX compliant.
expr1 expr2
Two expressions in a row are taken to be joined with an implied
-a; expr2 is not evaluated if expr1 is false.
expr1 -a expr2
Same as expr1 expr2.
expr1 -and expr2
Same as expr1 expr2, but not POSIX compliant.
expr1 -o expr2
Or; expr2 is not evaluated if expr1 is true.
expr1 -or expr2
Same as expr1 -o expr2, but not POSIX compliant.
expr1 , expr2
List; both expr1 and expr2 are always evaluated. The value of
expr1 is discarded; the value of the list is the value of expr2.
The comma operator can be useful for searching for several
different types of thing, but traversing the filesystem
hierarchy only once. The -fprintf action can be used to list
the various matched items into several different output files.
Please note that -a when specified implicitly (for example by two tests
appearing without an explicit operator between them) or explicitly has
higher precedence than -o. This means that find . -name afile -o -name
bfile -print will never print afile.
UNUSUAL FILENAMES
Many of the actions of find result in the printing of data which is
under the control of other users. This includes file names, sizes,
modification times and so forth. File names are a potential problem
since they can contain any character except `\0' and `/'. Unusual
characters in file names can do unexpected and often undesirable things
to your terminal (for example, changing the settings of your function
keys on some terminals). Unusual characters are handled differently by
various actions, as described below.
-print0, -fprint0
Always print the exact filename, unchanged, even if the output
is going to a terminal.
-ls, -fls
Unusual characters are always escaped. White space, backslash,
and double quote characters are printed using C-style escaping
(for example `\f', `\"'). Other unusual characters are printed
using an octal escape. Other printable characters (for -ls and
-fls these are the characters between octal 041 and 0176) are
printed as-is.
-printf, -fprintf
If the output is not going to a terminal, it is printed as-is.
Otherwise, the result depends on which directive is in use. The
directives %D, %F, %g, %G, %H, %Y, and %y expand to values which
are not under control of files' owners, and so are printed as-
is. The directives %a, %b, %c, %d, %i, %k, %m, %M, %n, %s, %t,
%u and %U have values which are under the control of files'
owners but which cannot be used to send arbitrary data to the
terminal, and so these are printed as-is. The directives %f,
%h, %l, %p and %P are quoted. This quoting is performed in the
same way as for GNU ls. This is not the same quoting mechanism
as the one used for -ls and -fls. If you are able to decide
what format to use for the output of find then it is normally
better to use `\0' as a terminator than to use newline, as file
names can contain white space and newline characters. The
setting of the `LC_CTYPE' environment variable is used to
determine which characters need to be quoted.
-print, -fprint
Quoting is handled in the same way as for -printf and -fprintf.
If you are using find in a script or in a situation where the
matched files might have arbitrary names, you should consider
using -print0 instead of -print.
The -ok and -okdir actions print the current filename as-is. This may
change in a future release.
STANDARDS CONFORMANCE
For closest compliance to the POSIX standard, you should set the
POSIXLY_CORRECT environment variable. The following options are
specified in the POSIX standard (IEEE Std 1003.1, 2003 Edition):
-H This option is supported.
-L This option is supported.
-name This option is supported, but POSIX conformance depends on the
POSIX conformance of the system's fnmatch(3) library function.
As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]'
for example) will match a leading `.', because IEEE PASC
interpretation 126 requires this. This is a change from
previous versions of findutils.
-type Supported. POSIX specifies `b', `c', `d', `l', `p', `f' and
`s'. GNU find also supports `D', representing a Door, where the
OS provides these. Furthermore, GNU find allows multiple types
to be specified at once in a comma-separated list.
-ok Supported. Interpretation of the response is according to the
`yes' and `no' patterns selected by setting the `LC_MESSAGES'
environment variable. When the `POSIXLY_CORRECT' environment
variable is set, these patterns are taken system's definition of
a positive (yes) or negative (no) response. See the system's
documentation for nl_langinfo(3), in particular YESEXPR and
NOEXPR. When `POSIXLY_CORRECT' is not set, the patterns are
instead taken from find's own message catalogue.
-newer Supported. If the file specified is a symbolic link, it is
always dereferenced. This is a change from previous behaviour,
which used to take the relevant time from the symbolic link; see
the HISTORY section below.
-perm Supported. If the POSIXLY_CORRECT environment variable is not
set, some mode arguments (for example +a+x) which are not valid
in POSIX are supported for backward-compatibility.
Other predicates
The predicates -atime, -ctime, -depth, -group, -links, -mtime,
-nogroup, -nouser, -print, -prune, -size, -user and -xdev
`-atime', `-ctime', `-depth', `-group', `-links', `-mtime',
`-nogroup', `-nouser', `-perm', `-print', `-prune', `-size',
`-user' and `-xdev', are all supported.
The POSIX standard specifies parentheses `(', `)', negation `!' and the
`and' and `or' operators ( -a, -o).
All other options, predicates, expressions and so forth are extensions
beyond the POSIX standard. Many of these extensions are not unique to
GNU find, however.
The POSIX standard requires that find detects loops:
The find utility shall detect infinite loops; that is, entering
a previously visited directory that is an ancestor of the last
file encountered. When it detects an infinite loop, find shall
write a diagnostic message to standard error and shall either
recover its position in the hierarchy or terminate.
GNU find complies with these requirements. The link count of
directories which contain entries which are hard links to an ancestor
will often be lower than they otherwise should be. This can mean that
GNU find will sometimes optimise away the visiting of a subdirectory
which is actually a link to an ancestor. Since find does not actually
enter such a subdirectory, it is allowed to avoid emitting a diagnostic
message. Although this behaviour may be somewhat confusing, it is
unlikely that anybody actually depends on this behaviour. If the leaf
optimisation has been turned off with -noleaf, the directory entry will
always be examined and the diagnostic message will be issued where it
is appropriate. Symbolic links cannot be used to create filesystem
cycles as such, but if the -L option or the -follow option is in use, a
diagnostic message is issued when find encounters a loop of symbolic
links. As with loops containing hard links, the leaf optimisation will
often mean that find knows that it doesn't need to call stat() or
chdir() on the symbolic link, so this diagnostic is frequently not
necessary.
The -d option is supported for compatibility with various BSD systems,
but you should use the POSIX-compliant option -depth instead.
The POSIXLY_CORRECT environment variable does not affect the behaviour
of the -regex or -iregex tests because those tests aren't specified in
the POSIX standard.
ENVIRONMENT VARIABLES
LANG Provides a default value for the internationalization variables
that are unset or null.
LC_ALL If set to a non-empty string value, override the values of all
the other internationalization variables.
LC_COLLATE
The POSIX standard specifies that this variable affects the
pattern matching to be used for the -name option. GNU find
uses the fnmatch(3) library function, and so support for
`LC_COLLATE' depends on the system library. This variable
also affects the interpretation of the response to -ok; while
the `LC_MESSAGES' variable selects the actual pattern used to
interpret the response to -ok, the interpretation of any bracket
expressions in the pattern will be affected by `LC_COLLATE'.
LC_CTYPE
This variable affects the treatment of character classes used in
regular expressions and also with the -name test, if the
system's fnmatch(3) library function supports this. This
variable also affects the interpretation of any character
classes in the regular expressions used to interpret the
response to the prompt issued by -ok. The `LC_CTYPE'
environment variable will also affect which characters are
considered to be unprintable when filenames are printed; see the
section UNUSUAL FILENAMES.
LC_MESSAGES
Determines the locale to be used for internationalised messages.
If the `POSIXLY_CORRECT' environment variable is set, this also
determines the interpretation of the response to the prompt made
by the -ok action.
NLSPATH
Determines the location of the internationalisation message
catalogues.
PATH Affects the directories which are searched to find the
executables invoked by -exec, -execdir, -ok and -okdir.
POSIXLY_CORRECT
Determines the block size used by -ls and -fls. If
POSIXLY_CORRECT is set, blocks are units of 512 bytes.
Otherwise they are units of 1024 bytes.
Setting this variable also turns off warning messages (that is,
implies -nowarn) by default, because POSIX requires that apart
from the output for -ok, all messages printed on stderr are
diagnostics and must result in a non-zero exit status.
When POSIXLY_CORRECT is not set, -perm +zzz is treated just like
-perm /zzz if +zzz is not a valid symbolic mode. When
POSIXLY_CORRECT is set, such constructs are treated as an error.
When POSIXLY_CORRECT is set, the response to the prompt made by
the -ok action is interpreted according to the system's message
catalogue, as opposed to according to find's own message
translations.
TZ Affects the time zone used for some of the time-related format
directives of -printf and -fprintf.
EXAMPLES
find /tmp -name core -type f -print | xargs /bin/rm -f Find files named core in or below the directory /tmp and delete them. Note that this will work incorrectly if there are any filenames containing newlines, single or double quotes, or spaces. find /tmp -name core -type f -print0 | xargs -0 /bin/rm -f Find files named core in or below the directory /tmp and delete them, processing filenames in such a way that file or directory names containing single or double quotes, spaces or newlines are correctly handled. The -name test comes before the -type test in order to avoid having to call stat(2) on every file. find . -type f -exec file '{}' \; Runs `file' on every file in or below the current directory. Notice that the braces are enclosed in single quote marks to protect them from interpretation as shell script punctuation. The semicolon is similarly protected by the use of a backslash, though single quotes could have been used in that case also. find / \( -perm -4000 -fprintf /root/suid.txt '%#m %u %p\n' \) , \ \( -size +100M -fprintf /root/big.txt '%-10s %p\n' \) Traverse the filesystem just once, listing setuid files and directories into /root/suid.txt and large files into /root/big.txt. find $HOME -mtime 0 Search for files in your home directory which have been modified in the last twenty-four hours. This command works this way because the time since each file was last modified is divided by 24 hours and any remainder is discarded. That means that to match -mtime 0, a file will have to have a modification in the past which is less than 24 hours ago. find /sbin /usr/sbin -executable \! -readable -print Search for files which are executable but not readable. find . -perm 664 Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched. find . -perm -664 Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). This will match a file which has mode 0777, for example. find . -perm /222 Search for files which are writable by somebody (their owner, or their group, or anybody else). find . -perm /220 find . -perm /u+w,g+w find . -perm /u=w,g=w All three of these commands do the same thing, but the first one uses the octal representation of the file mode, and the other two use the symbolic form. These commands all search for files which are writable by either their owner or their group. The files don't have to be writable by both the owner and group to be matched; either will do. find . -perm -220 find . -perm -g+w,u+w Both these commands do the same thing; search for files which are writable by both their owner and their group. find . -perm -444 -perm /222 \! -perm /111 find . -perm -a+r -perm /a+w \! -perm /a+x These two commands both search for files that are readable for everybody ( -perm -444 or -perm -a+r), have at least one write bit set ( -perm /222 or -perm /a+w) but are not executable for anybody ( ! -perm /111 and ! -perm /a+x respectively). cd /source-dir find . -name .snapshot -prune -o \( \! -name '*~' -print0 \)| cpio -pmd0 /dest-dir This command copies the contents of /source-dir to /dest-dir, but omits files and directories named .snapshot (and anything in them). It also omits files or directories whose name ends in ~, but not their contents. The construct -prune -o \( ... -print0 \) is quite common. The idea here is that the expression before -prune matches things which are to be pruned. However, the -prune action itself returns true, so the following -o ensures that the right hand side is evaluated only for those directories which didn't get pruned (the contents of the pruned directories are not even visited, so their contents are irrelevant). The expression on the right hand side of the -o is in parentheses only for clarity. It emphasises that the -print0 action takes place only for things that didn't have -prune applied to them. Because the default `and' condition between tests binds more tightly than -o, this is the default anyway, but the parentheses help to show what is going on. find repo/ \( -exec test -d '{}'/.svn \; -or \ -exec test -d {}/.git \; -or -exec test -d {}/CVS \; \) \ -print -prune Given the following directory of projects and their associated SCM administrative directories, perform an efficient search for the projects' roots: repo/project1/CVS repo/gnu/project2/.svn repo/gnu/project3/.svn repo/gnu/project3/src/.svn repo/project4/.git In this example, -prune prevents unnecessary descent into directories that have already been discovered (for example we do not search project3/src because we already found project3/.svn), but ensures sibling directories (project2 and project3) are found. find /tmp -type f,d,l Search for files, directories, and symbolic links in the directory /tmp passing these types as a comma-separated list (GNU extension), which is otherwise equivalent to the longer, yet more portable: find /tmp \( -type f -o -type d -o -type l \)
EXIT STATUS
find exits with status 0 if all files are processed successfully,
greater than 0 if errors occur. This is deliberately a very broad
description, but if the return value is non-zero, you should not rely
on the correctness of the results of find.
When some error occurs, find may stop immediately, without completing
all the actions specified. For example, some starting points may not
have been examined or some pending program invocations for -exec ... {}
+ or -execdir ... {} + may not have been performed.
SEE ALSO
locate(1), locatedb(5), updatedb(1), xargs(1), chmod(1), fnmatch(3), regex(7), stat(2), lstat(2), ls(1), printf(3), strftime(3), ctime(3) The full documentation for find is maintained as a Texinfo manual. If the info and find programs are properly installed at your site, the command info find should give you access to the complete manual.
HISTORY
As of findutils-4.2.2, shell metacharacters (`*', `?' or `[]' for example) used in filename patterns will match a leading `.', because IEEE POSIX interpretation 126 requires this. As of findutils-4.3.3, -perm /000 now matches all files instead of none. Nanosecond-resolution timestamps were implemented in findutils-4.3.3. As of findutils-4.3.11, the -delete action sets find's exit status to a nonzero value when it fails. However, find will not exit immediately. Previously, find's exit status was unaffected by the failure of -delete. Feature Added in Also occurs in -newerXY 4.3.3 BSD -D 4.3.1 -O 4.3.1 -readable 4.3.0 -writable 4.3.0 -executable 4.3.0 -regextype 4.2.24 -exec ... + 4.2.12 POSIX -execdir 4.2.12 BSD -okdir 4.2.12 -samefile 4.2.11 -H 4.2.5 POSIX -L 4.2.5 POSIX -P 4.2.5 BSD -delete 4.2.3 -quit 4.2.3 -d 4.2.3 BSD -wholename 4.2.0 -iwholename 4.2.0 -ignore_readdir_race 4.2.0 -fls 4.0 -ilname 3.8 -iname 3.8 -ipath 3.8 -iregex 3.8 The syntax -perm +MODE was removed in findutils-4.5.12, in favour of -perm /MODE. The +MODE syntax had been deprecated since findutils-4.2.21 which was released in 2005.
NON-BUGS
Operator precedence surprises The command find . -name afile -o -name bfile -print will never print afile because this is actually equivalent to find . -name afile -o \( -name bfile -a -print \). Remember that the precedence of -a is higher than that of -o and when there is no operator specified between tests, -a is assumed. "paths must precede expression" error message $ find . -name *.c -print find: paths must precede expression Usage: find [-H] [-L] [-P] [-Olevel] [-D ... [path...] [expression] This happens because *.c has been expanded by the shell resulting in find actually receiving a command line like this: find . -name frcode.c locate.c word_io.c -print That command is of course not going to work. Instead of doing things this way, you should enclose the pattern in quotes or escape the wildcard: $ find . -name '*.c' -print $ find . -name \*.c -print
BUGS
There are security problems inherent in the behaviour that the POSIX standard specifies for find, which therefore cannot be fixed. For example, the -exec action is inherently insecure, and -execdir should be used instead. Please see Finding Files for more information. The environment variable LC_COLLATE has no effect on the -ok action. The best way to report a bug is to use the form at http://savannah.gnu.org/bugs/?group=findutils. The reason for this is that you will then be able to track progress in fixing the problem. Other comments about find(1) and about the findutils package in general can be sent to the bug-findutils mailing list. To join the list, send email to bug-findutils-request@gnu.org. FIND(1)
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
