avprobe(1)
NAME
ffprobe - ffprobe media prober
SYNOPSIS
ffprobe [options] [input_url]
DESCRIPTION
ffprobe gathers information from multimedia streams and prints it in human- and machine-readable fashion. For example it can be used to check the format of the container used by a multimedia stream and the format and type of each media stream contained in it. If a url is specified in input, ffprobe will try to open and probe the url content. If the url cannot be opened or recognized as a multimedia file, a positive exit code is returned. ffprobe may be employed both as a standalone application or in combination with a textual filter, which may perform more sophisticated processing, e.g. statistical processing or plotting. Options are used to list some of the formats supported by ffprobe or for specifying which information to display, and for setting how ffprobe will show it. ffprobe output is designed to be easily parsable by a textual filter, and consists of one or more sections of a form defined by the selected writer, which is specified by the print_format option. Sections may contain other nested sections, and are identified by a name (which may be shared by other sections), and an unique name. See the output of sections. Metadata tags stored in the container or in the streams are recognized and printed in the corresponding "FORMAT", "STREAM" or "PROGRAM_STREAM" section.
OPTIONS
All the numerical options, if not specified otherwise, accept a string
representing a number as input, which may be followed by one of the SI
unit prefixes, for example: 'K', 'M', or 'G'.
If 'i' is appended to the SI unit prefix, the complete prefix will be
interpreted as a unit prefix for binary multiples, which are based on
powers of 1024 instead of powers of 1000. Appending 'B' to the SI unit
prefix multiplies the value by 8. This allows using, for example: 'KB',
'MiB', 'G' and 'B' as number suffixes.
Options which do not take arguments are boolean options, and set the
corresponding value to true. They can be set to false by prefixing the
option name with "no". For example using "-nofoo" will set the boolean
option with name "foo" to false.
Stream specifiers
Some options are applied per-stream, e.g. bitrate or codec. Stream
specifiers are used to precisely specify which stream(s) a given option
belongs to.
A stream specifier is a string generally appended to the option name
and separated from it by a colon. E.g. "-codec:a:1 ac3" contains the
"a:1" stream specifier, which matches the second audio stream.
Therefore, it would select the ac3 codec for the second audio stream.
A stream specifier can match several streams, so that the option is
applied to all of them. E.g. the stream specifier in "-b:a 128k"
matches all audio streams.
An empty stream specifier matches all streams. For example, "-codec
copy" or "-codec: copy" would copy all the streams without reencoding.
Possible forms of stream specifiers are:
stream_index
Matches the stream with this index. E.g. "-threads:1 4" would set
the thread count for the second stream to 4.
stream_type[:stream_index]
stream_type is one of following: 'v' or 'V' for video, 'a' for
audio, 's' for subtitle, 'd' for data, and 't' for attachments. 'v'
matches all video streams, 'V' only matches video streams which are
not attached pictures, video thumbnails or cover arts. If
stream_index is given, then it matches stream number stream_index
of this type. Otherwise, it matches all streams of this type.
p:program_id[:stream_index]
If stream_index is given, then it matches the stream with number
stream_index in the program with the id program_id. Otherwise, it
matches all streams in the program.
#stream_id or i:stream_id
Match the stream by stream id (e.g. PID in MPEG-TS container).
m:key[:value]
Matches streams with the metadata tag key having the specified
value. If value is not given, matches streams that contain the
given tag with any value.
u Matches streams with usable configuration, the codec must be
defined and the essential information such as video dimension or
audio sample rate must be present.
Note that in ffmpeg, matching by metadata will only work properly
for input files.
Generic options
These options are shared amongst the ff* tools.
-L Show license.
-h, -?, -help, --help [arg]
Show help. An optional parameter may be specified to print help
about a specific item. If no argument is specified, only basic (non
advanced) tool options are shown.
Possible values of arg are:
long
Print advanced tool options in addition to the basic tool
options.
full
Print complete list of options, including shared and private
options for encoders, decoders, demuxers, muxers, filters, etc.
decoder=decoder_name
Print detailed information about the decoder named
decoder_name. Use the -decoders option to get a list of all
decoders.
encoder=encoder_name
Print detailed information about the encoder named
encoder_name. Use the -encoders option to get a list of all
encoders.
demuxer=demuxer_name
Print detailed information about the demuxer named
demuxer_name. Use the -formats option to get a list of all
demuxers and muxers.
muxer=muxer_name
Print detailed information about the muxer named muxer_name.
Use the -formats option to get a list of all muxers and
demuxers.
filter=filter_name
Print detailed information about the filter name filter_name.
Use the -filters option to get a list of all filters.
-version
Show version.
-formats
Show available formats (including devices).
-devices
Show available devices.
-codecs
Show all codecs known to libavcodec.
Note that the term 'codec' is used throughout this documentation as
a shortcut for what is more correctly called a media bitstream
format.
-decoders
Show available decoders.
-encoders
Show all available encoders.
-bsfs
Show available bitstream filters.
-protocols
Show available protocols.
-filters
Show available libavfilter filters.
-pix_fmts
Show available pixel formats.
-sample_fmts
Show available sample formats.
-layouts
Show channel names and standard channel layouts.
-colors
Show recognized color names.
-sources device[,opt1=val1[,opt2=val2]...]
Show autodetected sources of the intput device. Some devices may
provide system-dependent source names that cannot be autodetected.
The returned list cannot be assumed to be always complete.
ffmpeg -sources pulse,server=192.168.0.4
-sinks device[,opt1=val1[,opt2=val2]...]
Show autodetected sinks of the output device. Some devices may
provide system-dependent sink names that cannot be autodetected.
The returned list cannot be assumed to be always complete.
ffmpeg -sinks pulse,server=192.168.0.4
-loglevel [repeat+]loglevel | -v [repeat+]loglevel
Set the logging level used by the library. Adding "repeat+"
indicates that repeated log output should not be compressed to the
first line and the "Last message repeated n times" line will be
omitted. "repeat" can also be used alone. If "repeat" is used
alone, and with no prior loglevel set, the default loglevel will be
used. If multiple loglevel parameters are given, using 'repeat'
will not change the loglevel. loglevel is a string or a number
containing one of the following values:
quiet, -8
Show nothing at all; be silent.
panic, 0
Only show fatal errors which could lead the process to crash,
such as an assertion failure. This is not currently used for
anything.
fatal, 8
Only show fatal errors. These are errors after which the
process absolutely cannot continue.
error, 16
Show all errors, including ones which can be recovered from.
warning, 24
Show all warnings and errors. Any message related to possibly
incorrect or unexpected events will be shown.
info, 32
Show informative messages during processing. This is in
addition to warnings and errors. This is the default value.
verbose, 40
Same as "info", except more verbose.
debug, 48
Show everything, including debugging information.
trace, 56
By default the program logs to stderr. If coloring is supported by
the terminal, colors are used to mark errors and warnings. Log
coloring can be disabled setting the environment variable
AV_LOG_FORCE_NOCOLOR or NO_COLOR, or can be forced setting the
environment variable AV_LOG_FORCE_COLOR. The use of the
environment variable NO_COLOR is deprecated and will be dropped in
a future FFmpeg version.
-report
Dump full command line and console output to a file named
"program-YYYYMMDD-HHMMSS.log" in the current directory. This file
can be useful for bug reports. It also implies "-loglevel
verbose".
Setting the environment variable FFREPORT to any value has the same
effect. If the value is a ':'-separated key=value sequence, these
options will affect the report; option values must be escaped if
they contain special characters or the options delimiter ':' (see
the ``Quoting and escaping'' section in the ffmpeg-utils manual).
The following options are recognized:
file
set the file name to use for the report; %p is expanded to the
name of the program, %t is expanded to a timestamp, "%%" is
expanded to a plain "%"
level
set the log verbosity level using a numerical value (see
"-loglevel").
For example, to output a report to a file named ffreport.log using
a log level of 32 (alias for log level "info"):
FFREPORT=file=ffreport.log:level=32 ffmpeg -i input output
Errors in parsing the environment variable are not fatal, and will
not appear in the report.
-hide_banner
Suppress printing banner.
All FFmpeg tools will normally show a copyright notice, build
options and library versions. This option can be used to suppress
printing this information.
-cpuflags flags (global)
Allows setting and clearing cpu flags. This option is intended for
testing. Do not use it unless you know what you're doing.
ffmpeg -cpuflags -sse+mmx ...
ffmpeg -cpuflags mmx ...
ffmpeg -cpuflags 0 ...
Possible flags for this option are:
x86
mmx
mmxext
sse
sse2
sse2slow
sse3
sse3slow
ssse3
atom
sse4.1
sse4.2
avx
avx2
xop
fma3
fma4
3dnow
3dnowext
bmi1
bmi2
cmov
ARM
armv5te
armv6
armv6t2
vfp
vfpv3
neon
setend
AArch64
armv8
vfp
neon
PowerPC
altivec
Specific Processors
pentium2
pentium3
pentium4
k6
k62
athlon
athlonxp
k8
-opencl_bench
This option is used to benchmark all available OpenCL devices and
print the results. This option is only available when FFmpeg has
been compiled with "--enable-opencl".
When FFmpeg is configured with "--enable-opencl", the options for
the global OpenCL context are set via -opencl_options. See the
"OpenCL Options" section in the ffmpeg-utils manual for the
complete list of supported options. Amongst others, these options
include the ability to select a specific platform and device to run
the OpenCL code on. By default, FFmpeg will run on the first device
of the first platform. While the options for the global OpenCL
context provide flexibility to the user in selecting the OpenCL
device of their choice, most users would probably want to select
the fastest OpenCL device for their system.
This option assists the selection of the most efficient
configuration by identifying the appropriate device for the user's
system. The built-in benchmark is run on all the OpenCL devices and
the performance is measured for each device. The devices in the
results list are sorted based on their performance with the fastest
device listed first. The user can subsequently invoke ffmpeg using
the device deemed most appropriate via -opencl_options to obtain
the best performance for the OpenCL accelerated code.
Typical usage to use the fastest OpenCL device involve the
following steps.
Run the command:
ffmpeg -opencl_bench
Note down the platform ID (pidx) and device ID (didx) of the first
i.e. fastest device in the list. Select the platform and device
using the command:
ffmpeg -opencl_options platform_idx=<pidx>:device_idx=<didx> ...
-opencl_options options (global)
Set OpenCL environment options. This option is only available when
FFmpeg has been compiled with "--enable-opencl".
options must be a list of key=value option pairs separated by ':'.
See the ``OpenCL Options'' section in the ffmpeg-utils manual for
the list of supported options.
AVOptions
These options are provided directly by the libavformat, libavdevice and
libavcodec libraries. To see the list of available AVOptions, use the
-help option. They are separated into two categories:
generic
These options can be set for any container, codec or device.
Generic options are listed under AVFormatContext options for
containers/devices and under AVCodecContext options for codecs.
private
These options are specific to the given container, device or codec.
Private options are listed under their corresponding
containers/devices/codecs.
For example to write an ID3v2.3 header instead of a default ID3v2.4 to
an MP3 file, use the id3v2_version private option of the MP3 muxer:
ffmpeg -i input.flac -id3v2_version 3 out.mp3
All codec AVOptions are per-stream, and thus a stream specifier should
be attached to them.
Note: the -nooption syntax cannot be used for boolean AVOptions, use
-option 0/-option 1.
Note: the old undocumented way of specifying per-stream AVOptions by
prepending v/a/s to the options name is now obsolete and will be
removed soon.
Main options
-f format
Force format to use.
-unit
Show the unit of the displayed values.
-prefix
Use SI prefixes for the displayed values. Unless the
"-byte_binary_prefix" option is used all the prefixes are decimal.
-byte_binary_prefix
Force the use of binary prefixes for byte values.
-sexagesimal
Use sexagesimal format HH:MM:SS.MICROSECONDS for time values.
-pretty
Prettify the format of the displayed values, it corresponds to the
options "-unit -prefix -byte_binary_prefix -sexagesimal".
-of, -print_format writer_name[=writer_options]
Set the output printing format.
writer_name specifies the name of the writer, and writer_options
specifies the options to be passed to the writer.
For example for printing the output in JSON format, specify:
-print_format json
For more details on the available output printing formats, see the
Writers section below.
-sections
Print sections structure and section information, and exit. The
output is not meant to be parsed by a machine.
-select_streams stream_specifier
Select only the streams specified by stream_specifier. This option
affects only the options related to streams (e.g. "show_streams",
"show_packets", etc.).
For example to show only audio streams, you can use the command:
ffprobe -show_streams -select_streams a INPUT
To show only video packets belonging to the video stream with index
1:
ffprobe -show_packets -select_streams v:1 INPUT
-show_data
Show payload data, as a hexadecimal and ASCII dump. Coupled with
-show_packets, it will dump the packets' data. Coupled with
-show_streams, it will dump the codec extradata.
The dump is printed as the "data" field. It may contain newlines.
-show_data_hash algorithm
Show a hash of payload data, for packets with -show_packets and for
codec extradata with -show_streams.
-show_error
Show information about the error found when trying to probe the
input.
The error information is printed within a section with name
"ERROR".
-show_format
Show information about the container format of the input multimedia
stream.
All the container format information is printed within a section
with name "FORMAT".
-show_format_entry name
Like -show_format, but only prints the specified entry of the
container format information, rather than all. This option may be
given more than once, then all specified entries will be shown.
This option is deprecated, use "show_entries" instead.
-show_entries section_entries
Set list of entries to show.
Entries are specified according to the following syntax.
section_entries contains a list of section entries separated by
":". Each section entry is composed by a section name (or unique
name), optionally followed by a list of entries local to that
section, separated by ",".
If section name is specified but is followed by no "=", all entries
are printed to output, together with all the contained sections.
Otherwise only the entries specified in the local section entries
list are printed. In particular, if "=" is specified but the list
of local entries is empty, then no entries will be shown for that
section.
Note that the order of specification of the local section entries
is not honored in the output, and the usual display order will be
retained.
The formal syntax is given by:
<LOCAL_SECTION_ENTRIES> ::= <SECTION_ENTRY_NAME>[,<LOCAL_SECTION_ENTRIES>]
<SECTION_ENTRY> ::= <SECTION_NAME>[=[<LOCAL_SECTION_ENTRIES>]]
<SECTION_ENTRIES> ::= <SECTION_ENTRY>[:<SECTION_ENTRIES>]
For example, to show only the index and type of each stream, and
the PTS time, duration time, and stream index of the packets, you
can specify the argument:
packet=pts_time,duration_time,stream_index : stream=index,codec_type
To show all the entries in the section "format", but only the codec
type in the section "stream", specify the argument:
format : stream=codec_type
To show all the tags in the stream and format sections:
stream_tags : format_tags
To show only the "title" tag (if available) in the stream sections:
stream_tags=title
-show_packets
Show information about each packet contained in the input
multimedia stream.
The information for each single packet is printed within a
dedicated section with name "PACKET".
-show_frames
Show information about each frame and subtitle contained in the
input multimedia stream.
The information for each single frame is printed within a dedicated
section with name "FRAME" or "SUBTITLE".
-show_streams
Show information about each media stream contained in the input
multimedia stream.
Each media stream information is printed within a dedicated section
with name "STREAM".
-show_programs
Show information about programs and their streams contained in the
input multimedia stream.
Each media stream information is printed within a dedicated section
with name "PROGRAM_STREAM".
-show_chapters
Show information about chapters stored in the format.
Each chapter is printed within a dedicated section with name
"CHAPTER".
-count_frames
Count the number of frames per stream and report it in the
corresponding stream section.
-count_packets
Count the number of packets per stream and report it in the
corresponding stream section.
-read_intervals read_intervals
Read only the specified intervals. read_intervals must be a
sequence of interval specifications separated by ",". ffprobe will
seek to the interval starting point, and will continue reading from
that.
Each interval is specified by two optional parts, separated by "%".
The first part specifies the interval start position. It is
interpreted as an absolute position, or as a relative offset from
the current position if it is preceded by the "+" character. If
this first part is not specified, no seeking will be performed when
reading this interval.
The second part specifies the interval end position. It is
interpreted as an absolute position, or as a relative offset from
the current position if it is preceded by the "+" character. If the
offset specification starts with "#", it is interpreted as the
number of packets to read (not including the flushing packets) from
the interval start. If no second part is specified, the program
will read until the end of the input.
Note that seeking is not accurate, thus the actual interval start
point may be different from the specified position. Also, when an
interval duration is specified, the absolute end time will be
computed by adding the duration to the interval start point found
by seeking the file, rather than to the specified start value.
The formal syntax is given by:
<INTERVAL> ::= [<START>|+<START_OFFSET>][%[<END>|+<END_OFFSET>]]
<INTERVALS> ::= <INTERVAL>[,<INTERVALS>]
A few examples follow.
* Seek to time 10, read packets until 20 seconds after the found
seek point, then seek to position "01:30" (1 minute and thirty
seconds) and read packets until position "01:45".
10%+20,01:30%01:45
* Read only 42 packets after seeking to position "01:23":
01:23%+#42
* Read only the first 20 seconds from the start:
%+20
* Read from the start until position "02:30":
%02:30
-show_private_data, -private
Show private data, that is data depending on the format of the
particular shown element. This option is enabled by default, but
you may need to disable it for specific uses, for example when
creating XSD-compliant XML output.
-show_program_version
Show information related to program version.
Version information is printed within a section with name
"PROGRAM_VERSION".
-show_library_versions
Show information related to library versions.
Version information for each library is printed within a section
with name "LIBRARY_VERSION".
-show_versions
Show information related to program and library versions. This is
the equivalent of setting both -show_program_version and
-show_library_versions options.
-show_pixel_formats
Show information about all pixel formats supported by FFmpeg.
Pixel format information for each format is printed within a
section with name "PIXEL_FORMAT".
-bitexact
Force bitexact output, useful to produce output which is not
dependent on the specific build.
-i input_url
Read input_url.
WRITERS
A writer defines the output format adopted by ffprobe, and will be used
for printing all the parts of the output.
A writer may accept one or more arguments, which specify the options to
adopt. The options are specified as a list of key=value pairs,
separated by ":".
All writers support the following options:
string_validation, sv
Set string validation mode.
The following values are accepted.
fail
The writer will fail immediately in case an invalid string
(UTF-8) sequence or code point is found in the input. This is
especially useful to validate input metadata.
ignore
Any validation error will be ignored. This will result in
possibly broken output, especially with the json or xml writer.
replace
The writer will substitute invalid UTF-8 sequences or code
points with the string specified with the
string_validation_replacement.
Default value is replace.
string_validation_replacement, svr
Set replacement string to use in case string_validation is set to
replace.
In case the option is not specified, the writer will assume the
empty string, that is it will remove the invalid sequences from the
input strings.
A description of the currently available writers follows.
default
Default format.
Print each section in the form:
[SECTION]
key1=val1
...
keyN=valN
[/SECTION]
Metadata tags are printed as a line in the corresponding FORMAT, STREAM
or PROGRAM_STREAM section, and are prefixed by the string "TAG:".
A description of the accepted options follows.
nokey, nk
If set to 1 specify not to print the key of each field. Default
value is 0.
noprint_wrappers, nw
If set to 1 specify not to print the section header and footer.
Default value is 0.
compact, csv
Compact and CSV format.
The "csv" writer is equivalent to "compact", but supports different
defaults.
Each section is printed on a single line. If no option is specifid,
the output has the form:
section|key1=val1| ... |keyN=valN
Metadata tags are printed in the corresponding "format" or "stream"
section. A metadata tag key, if printed, is prefixed by the string
"tag:".
The description of the accepted options follows.
item_sep, s
Specify the character to use for separating fields in the output
line. It must be a single printable character, it is "|" by
default ("," for the "csv" writer).
nokey, nk
If set to 1 specify not to print the key of each field. Its default
value is 0 (1 for the "csv" writer).
escape, e
Set the escape mode to use, default to "c" ("csv" for the "csv"
writer).
It can assume one of the following values:
c Perform C-like escaping. Strings containing a newline (\n),
carriage return (\r), a tab (\t), a form feed (\f), the
escaping character (\) or the item separator character SEP are
escaped using C-like fashioned escaping, so that a newline is
converted to the sequence \n, a carriage return to \r, \ to \\
and the separator SEP is converted to \SEP.
csv Perform CSV-like escaping, as described in RFC4180. Strings
containing a newline (\n), a carriage return (\r), a double
quote ("), or SEP are enclosed in double-quotes.
none
Perform no escaping.
print_section, p
Print the section name at the begin of each line if the value is 1,
disable it with value set to 0. Default value is 1.
flat
Flat format.
A free-form output where each line contains an explicit key=value, such
as "streams.stream.3.tags.foo=bar". The output is shell escaped, so it
can be directly embedded in sh scripts as long as the separator
character is an alphanumeric character or an underscore (see sep_char
option).
The description of the accepted options follows.
sep_char, s
Separator character used to separate the chapter, the section name,
IDs and potential tags in the printed field key.
Default value is ..
hierarchical, h
Specify if the section name specification should be hierarchical.
If set to 1, and if there is more than one section in the current
chapter, the section name will be prefixed by the name of the
chapter. A value of 0 will disable this behavior.
Default value is 1.
ini
INI format output.
Print output in an INI based format.
The following conventions are adopted:
* all key and values are UTF-8
* . is the subgroup separator
* newline, \t, \f, and the following characters are escaped
* \ is the escape character
* # is the comment indicator
* = is the key/value separator
* : is not used but usually parsed as key/value separator
This writer accepts options as a list of key=value pairs, separated by
:.
The description of the accepted options follows.
hierarchical, h
Specify if the section name specification should be hierarchical.
If set to 1, and if there is more than one section in the current
chapter, the section name will be prefixed by the name of the
chapter. A value of 0 will disable this behavior.
Default value is 1.
json
JSON based format.
Each section is printed using JSON notation.
The description of the accepted options follows.
compact, c
If set to 1 enable compact output, that is each section will be
printed on a single line. Default value is 0.
For more information about JSON, see <http://www.json.org/>.
xml
XML based format.
The XML output is described in the XML schema description file
ffprobe.xsd installed in the FFmpeg datadir.
An updated version of the schema can be retrieved at the url
<http://www.ffmpeg.org/schema/ffprobe.xsd>, which redirects to the
latest schema committed into the FFmpeg development source code tree.
Note that the output issued will be compliant to the ffprobe.xsd schema
only when no special global output options (unit, prefix,
byte_binary_prefix, sexagesimal etc.) are specified.
The description of the accepted options follows.
fully_qualified, q
If set to 1 specify if the output should be fully qualified.
Default value is 0. This is required for generating an XML file
which can be validated through an XSD file.
xsd_compliant, x
If set to 1 perform more checks for ensuring that the output is XSD
compliant. Default value is 0. This option automatically sets
fully_qualified to 1.
For more information about the XML format, see
<http://www.w3.org/XML/>.
TIMECODE
ffprobe supports Timecode extraction:
* MPEG1/2 timecode is extracted from the GOP, and is available in the
video stream details (-show_streams, see timecode).
* MOV timecode is extracted from tmcd track, so is available in the
tmcd stream metadata (-show_streams, see TAG:timecode).
* DV, GXF and AVI timecodes are available in format metadata
(-show_format, see TAG:timecode).
SEE ALSO
ffprobe-all(1), ffmpeg(1), ffplay(1), ffserver(1), ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1), ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1), ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1)
AUTHORS
The FFmpeg developers.
For details about the authorship, see the Git history of the project
(git://source.ffmpeg.org/ffmpeg), e.g. by typing the command git log in
the FFmpeg source directory, or browsing the online repository at
<http://source.ffmpeg.org>.
Maintainers for the specific components are listed in the file
MAINTAINERS in the source code tree.
FFPROBE(1)
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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.
