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mkfifo(3)
NAME
  mkfifo - Creates a FIFO

LIBRARY
  Standard C Library (libc.a)
  System V Compatibility Library (libsys5.a)

SYNOPSIS
  #include <sys/types.h>
  #include <sys/stat.h>

  int mkfifo (
	  const char *path,
	  mode_t mode );

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  mkfifo():  POSIX.1, XPG4, XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  path	    Names the new file.	 If the final component of the path parameter
	    names a symbolic link, the link will be traversed and pathname
	    resolution will continue.

  mode	    Specifies the type, attributes, and access permissions of the
	    file.  This parameter is constructed by logically ORing values
	    described in the sys/mode.h header file.

	    The mode is then modified by the current file mode creation mask
	    (umask) value.

DESCRIPTION
  The mkfifo function used with libc.a is an interface to the mknod function,
  where the file that is to be created is a FIFO special file.

  When used with libsys5.a, the mkfifo() function creates a uni-directional
  STREAMS based file descriptor.  The FIFO created is represented in the file
  system as a character special file.

  No special system privileges are required under either implementation.


  Upon successful completion, the mkfifo() function marks the st_atime,
  st_ctime, and st_mtime fields of the file for update, and sets the st_ctime
  and st_mtime fields of the directory that contains the new entry for
  update.


RETURN VALUES
  Upon successful completion of mkfifo(), a value of 0 (zero) is returned.
  Otherwise, a value of -1 is returned and errno is set to indicate the
  error.

ERRORS
  If the mkfifo() function fails, the new file is not created and errno may
  be set to one of the following values:

  [EACCES]  A component of the path prefix denies search permission, or write
	    permission is denied on the parent directory of the FIFO to be
	    created.

  [EDQUOT]  The directory in which the entry for the new link is being placed
	    cannot be extended because the user's quota of disk blocks or
	    inodes on the file system is exhausted.

  [EEXIST]  The named file exists.

  [ELOOP]   Too many links were encountered in translating path.

  [EMFILE]  No more file descriptors are available for this process.

  [EMFILE]  The system file table is full, or the device containing the pipes
	    has no free inodes.

  [ENAMETOOLONG]
	    The length of the path parameter exceeds PATH_MAX or a pathname
	    component is longer than NAME_MAX.

  [ENOENT]  A component of the path prefix does not exist or the path
	    parameter points to an empty string.

  [ENOSPC]  The directory that would contain the new file cannot be extended
	    or the file system is out of file allocation resources.

  [ENOTDIR] A component of the path prefix is not a directory.

  [EPERM]   The mode parameter specifies a file type other than S_IFIFO and
	    the calling process does not have the DEV_CONFIG system
	    privilege.

  [EROFS]   The directory in which the file is to be created is located on a
	    read-only file system.

RELATED INFORMATION
  Commands: chmod(1), mkdir(1), mkfifo(1)

  Functions: chmod(2), mkdir(2), mknod(2), open(2), stat(2), umask(2)

  Standards: standards(5)