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MKFIFO(2)                     System Calls Manual                    MKFIFO(2)

NAME
     mkfifo, mkfifoat - make a fifo file

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/stat.h>

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

     #include <sys/stat.h>
     #include <fcntl.h>

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

DESCRIPTION
     mkfifo() 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.

     mkfifoat() works the same way as mkfifo() except if path is relative.  In
     that case, it is looked up from a directory whose file descriptor was
     passed as fd.  Search permission is required on this directory.  fd can
     be set to AT_FDCWD in order to specify the current directory.

     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.

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

ERRORS
     mkfifo() and mkfifoat() will fail and no fifo will be created if:

     [EACCES]           Search permission is denied for a component of the
                        path prefix.

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

     [EEXIST]           The named file exists.

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

     [EIO]              An I/O error occurred while making the directory entry
                        or allocating the inode.  Or, an I/O error occurred
                        while reading from or writing to the file system.

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

     [ENAMETOOLONG]     A component of a pathname exceeded {NAME_MAX}
                        characters, or an entire path name exceeded {PATH_MAX}
                        characters.

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

     [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.  Or, there are no free inodes on the file
                        system on which the fifo is being created.

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

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

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

     In addition, mkfifoat() will fail if:

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

     [ENOTDIR]          path is not an absolute path and fd is a file
                        descriptor associated with a non-directory file.

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

STANDARDS
     The mkfifo function call conforms to IEEE Std 1003.1-1990 ("POSIX.1").
     mkfifoat() conforms to IEEE Std 1003.1-2008 ("POSIX.1").

NetBSD 10.99                     July 29, 2013                    NetBSD 10.99