mkfifo - Creates a FIFO
Standard C Library (libc.a)
System V Compatibility Library (libsys5.a)
#include <sys/types.h> #include <sys/stat.h>
int mkfifo (
const char *path,
mode_t mode );
Interfaces documented on this reference page conform to industry standards as follows:
mkfifo(): POSIX.1, XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about industry standards and associated tags.
Names the new file. If the final component of the path parameter names a symbolic link, the link will be traversed and pathname resolution will continue. Specifies the type, attributes, and access permissions of the file. This parameter is constructed by logically ORing values described in the sys/mode.h header file.
The mkfifo function used with libc.a is an interface to the mknod function, where the file that is to be created is a FIFO special file.
When used with libsys5.a, the mkfifo() function creates a uni-directional STREAMS based file descriptor. The FIFO created is represented in the file system as a character special file.
No special system privileges are required under either implementation.
Upon successful completion, the mkfifo() function marks the st_atime, st_ctime, and st_mtime fields of the file for update, and sets the st_ctime and st_mtime fields of the directory that contains the new entry for update.
Upon successful completion of mkfifo(), a value of 0 (zero) is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error.
If the mkfifo() function fails, the new file is not created and errno may be set to one of the following values: A component of the path prefix denies search permission, or write permission is denied on the parent directory of the FIFO to be created. The directory in which the entry for the new link is being placed cannot be extended because the user's quota of disk blocks or inodes on the file system is exhausted. The named file exists. Too many links were encountered in translating path. No more file descriptors are available for this process. The system file table is full, or the device containing the pipes has no free inodes. The length of the path parameter exceeds PATH_MAX or a pathname component is longer than NAME_MAX. A component of the path prefix does not exist or the path parameter points to an empty string. The directory that would contain the new file cannot be extended or the file system is out of file allocation resources. A component of the path prefix is not a directory. The mode parameter specifies a file type other than S_IFIFO and the calling process does not have the DEV_CONFIG system privilege. The directory in which the file is to be created is located on a read-only file system.
Commands: chmod(1), mkdir(1), mkfifo(1)
Functions: chmod(2), mkdir(2), mknod(2), open(2), stat(2), umask(2)