mkfifo - make a FIFO special file (a named pipe)
#include <sys/types.h>
#include <sys/stat.h>
int mkfifo ( const char *pathname, mode_t mode );
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.
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).
EACCES One of the directories in pathname did not allow search (execute)
permission.
EEXIST pathname already exists.
ENAMETOOLONG [Toc] [Back]
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 [Toc] [Back]
A component used as a directory in pathname is not, in fact, a
directory.
EROFS pathname refers to a read-only filesystem.
POSIX.1
mkfifo(1), read(2), write(2), open(2), close(2), stat(2), umask(2),
fifo(4)
Linux 1.2.13 1995-09-03 MKFIFO(3)
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