mkfifo(3C) Standard C Library Functions mkfifo(3C)
NAME
mkfifo - make a FIFO special file
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
int mkfifo(const char *path, mode_t mode);
DESCRIPTION
The mkfifo() function creates a new FIFO special file named by the pathname pointed to by path. The file permission bits of the new FIFO
are initialized from mode. The file permission bits of the mode argument are modified by the process's file creation mask (see umask(2)).
Bits other than the file permission bits in mode are ignored.
If path names a symbolic link, mkfifo() fails and sets errno to EEXIST.
The FIFO's user ID is set to the process's effective user ID. The FIFO's group ID is set to the group ID of the parent directory or to the
effective group ID of the process.
The mkfifo() function calls mknod(2) to create the file.
Upon successful completion, mkfifo() marks for update the st_atime, st_ctime, and st_mtime fields of the file. Also, the st_ctime and
st_mtime fields of the directory that contains the new entry are marked for update.
RETURN VALUES
Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error.
ERRORS
The mkfifo() function will fail if:
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.
EEXIST The named file already exists.
ELOOP A loop exists in symbolic links encountered during resolution of the path argument.
ENAMETOOLONG The length of the path argument exceeds {PATH_MAX} or a pathname component is longer than {NAME_MAX}.
ENOENT A component of the path prefix specified by path does not name an existing directory or path is an empty string.
ENOSPC The directory that would contain the new file cannot be extended or the file system is out of file-allocation resources.
ENOTDIR A component of the path prefix is not a directory.
EROFS The named file resides on a read-only file system.
The mkfifo() function may fail if:
ELOOP Too many symbolic links were encountered in resolving path.
ENAMETOOLONG The length of the path argument exceeds {PATH_MAX} or a pathname component is longer than {NAME_MAX}.
EXAMPLES
Example 1 Create a FIFO File
The following example demonstrates how to create a FIFO file named /home/cnd/mod_done with read and write permissions for the owner and
read permissions for the group and others.
#include sys/types.h>
#include sys/stat.h>
int status;
...
status = mkfifo("/home/cnd/mod_done", S_IWUSR | S_IRUSR |
S_IRGRP | S_IROTH);
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
SEE ALSO
mkdir(1), chmod(2), exec(2), mknod(2), umask(2), stat.h(3HEAD), ufs(7FS), attributes(5), standards(5)
SunOS 5.11 24 Apr 2002 mkfifo(3C)