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 anony­
       mous  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)