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opendir(3)


NAME

   opendir, fdopendir - open a directory

SYNOPSIS

   #include <sys/types.h>
   #include <dirent.h>

   DIR *opendir(const char *name);
   DIR *fdopendir(int fd);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

   fdopendir():
       Since glibc 2.10:
           _POSIX_C_SOURCE >= 200809L
       Before glibc 2.10:
           _GNU_SOURCE

DESCRIPTION

   The  opendir()  function  opens a directory stream corresponding to the
   directory name, and returns a pointer to  the  directory  stream.   The
   stream is positioned at the first entry in the directory.

   The  fdopendir()  function  is  like opendir(), but returns a directory
   stream for the directory referred to by the open  file  descriptor  fd.
   After  a  successful  call to fdopendir(), fd is used internally by the
   implementation, and should not otherwise be used by the application.

RETURN VALUE

   The opendir()  and  fdopendir()  functions  return  a  pointer  to  the
   directory  stream.   On  error,  NULL  is  returned,  and  errno is set
   appropriately.

ERRORS

   EACCES Permission denied.

   EBADF  fd is not a valid file descriptor opened for reading.

   EMFILE The per-process limit on the number of open file descriptors has
          been reached.

   ENFILE The system-wide limit on the total number of open files has been
          reached.

   ENOENT Directory does not exist, or name is an empty string.

   ENOMEM Insufficient memory to complete the operation.

   ENOTDIR
          name is not a directory.

VERSIONS

   fdopendir() is available in glibc since version 2.4.

ATTRIBUTES

   For  an  explanation  of  the  terms  used   in   this   section,   see
   attributes(7).

   ┌───────────────────────┬───────────────┬─────────┐
   │Interface              │ Attribute     │ Value   │
   ├───────────────────────┼───────────────┼─────────┤
   │opendir(), fdopendir() │ Thread safety │ MT-Safe │
   └───────────────────────┴───────────────┴─────────┘

CONFORMING TO

   opendir()  is  present  on SVr4, 4.3BSD, and specified in POSIX.1-2001.
   fdopendir() is specified in POSIX.1-2008.

NOTES

   Filename entries can be read from a directory stream using readdir(3).

   The underlying file descriptor of the directory stream can be  obtained
   using dirfd(3).

   The  opendir()  function  sets  the  close-on-exec  flag  for  the file
   descriptor underlying the DIR *.  The fdopendir() function  leaves  the
   setting  of  the  close-on-exec flag unchanged for the file descriptor,
   fd.  POSIX.1-200x leaves it unspecified whether a  successful  call  to
   fdopendir()  will  set  the close-on-exec flag for the file descriptor,
   fd.

SEE ALSO

   open(2), closedir(3), dirfd(3), readdir(3),  rewinddir(3),  scandir(3),
   seekdir(3), telldir(3)

COLOPHON

   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at
   https://www.kernel.org/doc/man-pages/.



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