MKFIFO(2)                 FreeBSD System Calls Manual                MKFIFO(2)

NAME
     mkfifo, mkfifoat - make a fifo file

LIBRARY
     Standard C Library (libc, -lc)

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

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

     int
     mkfifoat(int fd, const char *path, mode_t mode);

DESCRIPTION
     The mkfifo() system call creates a new fifo file with name path.  The
     access permissions are specified by mode and restricted by the umask(2)
     of the calling process.

     The fifo's owner ID is set to the process's effective user ID.  The
     fifo's group ID is set to that of the parent directory in which it is
     created.

     The mkfifoat() system call is equivalent to mkfifo() except in the case
     where path specifies a relative path.  In this case the newly created
     FIFO is created relative to the directory associated with the file
     descriptor fd instead of the current working directory.  If mkfifoat() is
     passed the special value AT_FDCWD in the fd parameter, the current
     working directory is used and the behavior is identical to a call to
     mkfifo().

RETURN VALUES
     The mkfifo() function returns the value 0 if successful; otherwise the
     value -1 is returned and the global variable errno is set to indicate the
     error.

ERRORS
     The mkfifo() system call will fail and no fifo will be created if:

     [ENOTSUP]          The kernel has not been configured to support fifo's.

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

     [ENAMETOOLONG]     A component of a pathname exceeded 255 characters, or
                        an entire path name exceeded 1023 characters.

     [ENOENT]           A component of the path prefix does not exist.

     [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.

     [ELOOP]            Too many symbolic links were encountered in
                        translating the pathname.

     [EROFS]            The named file would reside on a read-only file
                        system.

     [EEXIST]           The named file exists.

     [EPERM]            The parent directory of the named file has its
                        immutable flag set, see the chflags(2) manual page for
                        more information.

     [ENOSPC]           The directory in which the entry for the new fifo is
                        being placed cannot be extended because there is no
                        space left on the file system containing the
                        directory.

     [ENOSPC]           There are no free inodes on the file system on which
                        the fifo is being created.

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

     [EDQUOT]           The user's quota of inodes on the file system on which
                        the fifo is being created has been exhausted.

     [EIO]              An I/O error occurred while making the directory entry
                        or allocating the inode.

     [EINTEGRITY]       Corrupted data was detected while reading from the
                        file system.

     [EFAULT]           The path argument points outside the process's
                        allocated address space.

     In addition to the errors returned by the mkfifo(), the mkfifoat() may
     fail if:

     [EBADF]            The path argument does not specify an absolute path
                        and the fd argument is neither AT_FDCWD nor a valid
                        file descriptor open for searching.

     [ENOTDIR]          The path argument is not an absolute path and fd is
                        neither AT_FDCWD nor a file descriptor associated with
                        a directory.

SEE ALSO
     chflags(2), chmod(2), mknod(2), stat(2), umask(2)

STANDARDS
     The mkfifo() system call is expected to conform to IEEE Std 1003.1-1990
     ("POSIX.1").  The mkfifoat() system call follows The Open Group Extended
     API Set 2 specification.

HISTORY
     The mkfifoat() system call appeared in FreeBSD 8.0.

FreeBSD 13.1-RELEASE-p6         March 30, 2020         FreeBSD 13.1-RELEASE-p6