mkfifo

MKFIFO(3)                   Linux Programmer's Manual                  MKFIFO(3)



NAME
       mkfifo - make a FIFO special file (a named pipe)

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

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

DESCRIPTION
       mkfifo makes a FIFO special file with name pathname.  mode specifies the
       FIFO's permissions. It is modified by the process's umask in the usual
       way: the permissions of the created file are (mode & ~umask).

       A FIFO special file is similar to a pipe, except that it is created in a
       different way.  Instead of being an anonymous communications channel, a
       FIFO special file is entered into the file system by calling mkfifo.

       Once you have created a FIFO special file in this way, any process can
       open it for reading or writing, in the same way as an ordinary file.
       However, it has to be open at both ends simultaneously before you can
       proceed to do any input or output operations on it.  Opening a FIFO for
       reading normally blocks until some other process opens the same FIFO for
       writing, and vice versa. See fifo(4) for non-blocking handling of FIFO
       special files.

RETURN VALUE
       The normal, successful return value from mkfifo is 0.  In the case of an
       error, -1 is returned (in which case, errno is set appropriately).

ERRORS
       EACCES One of the directories in pathname did not allow search (execute)
              permission.

       EEXIST pathname already exists.

       ENAMETOOLONG
              Either the total length of pathname is greater than PATH_MAX, or
              an individual file name component has a length greater than
              NAME_MAX.  In the GNU system, there is no imposed limit on overall
              file name length, but some file systems may place limits on the
              length of a component.

       ENOENT A directory component in pathname does not exist or is a dangling
              symbolic link.

       ENOSPC The directory or filesystem has no room for the new file.

       ENOTDIR
              A component used as a directory in pathname is not, in fact, a
              directory.

       EROFS  pathname refers to a read-only filesystem.

CONFORMING TO
       POSIX.1

SEE ALSO
       mkfifo(1), read(2), write(2), open(2), close(2), stat(2), umask(2),
       fifo(4)



Linux 1.2.13                    3 September 1995                       MKFIFO(3)