HP 3000 Manuals HP 3000 Manuals
mkfifo
Make a FIFO special file.
Syntax
#include <sys/types.h>
#include <sys/stat.h>
int mkfifo (const char *path, mode_t mode);
Parameters
path The pathname of a file.
mode The access permission bits for the new directory.
Access permission bits are set by ORing any
combination of the following macros:
S_IRWXU Set file owner class read, write, and
execute (if a file) or search (if a
directory) permission bits.
S_IRUSR Set file owner class read permission
bit.
S_IWUSR Set file owner class write permission
bit.
S_IXUSR Set file owner class execute (if a
file) or search (if a directory)
permission bit.
S_IRWXG Set file group class read, write, and
execute (if a file) or search (if a
directory) permission bits.
S_IRGRP Set file group class read permission
bit.
S_IWGRP Set file group class write permission
bit.
S_IXGRP Set file group class execute (if a
file) or search (if a directory)
permission bit.
S_IRWXO Set file other class read, write, and
execute (if a file), or searc h (if a
directory) permission bits.
S_IROTH Set file other class read permission
bit.
S_IWOTH Set file other class write permission
bit.
S_IXOTH Set file other class execute (if a
file) or search (if a directory)
permission bit.
Unused bits of the mode parameter not associated
with access permissions must contain zeros or an
error occurs.
Return Values
0 Successful completion
-1 No FIFO is created, and errno is set to indicate
the error.
Description
The mkfifo() routine creats a new FIFO special file named by the pathname
pointed to by path. The file permission bits of th enew FIFO are
initialized from mode. The fil epermission bits of the moide argument
are modified by the fiel creation mask of the process. When bits in mode
other than the file permission bits are set, the effect is implementation
defined.
The owner ID of the FIFO shall be set to the effective user ID of the
process. The group ID of the FIFO shall be set to the group ID of the
directory in which the FIFO is being created or to the effective group ID
of the process.
Upon successful completion, the mkfifo() function shall mark for update
the st_atime, st_ctime, and st_mtime% fields of the file. Also, the
st_ctime and the st_mtime fields of the directory taht contains the new
entry are ;marked for update.
Implementation Considerations
None.
Errors
If any of the following conditions occur, the mkfifi9() function returns
-1 and sets errno to the corresponding value.
EACCES CAUSE Serach permission is denied on a compoenent of the
path prefix, or wirte permission is denied on the
parent directory of the file to be created.
ACTION Make sure that the calling process has search
permission for all components of the pathname and
write permission to the parent directory.
EEXIST CAUSE The named file already exists.
ACTION Make sure that pathname specifies a directory that
does not already exist.
ENAMETOOLONG CAUSE The length of the path string exceeds [PATH_MAX] , or
a pathname component is larger thatn [NAME_MAX] while
{_POSIX_NO)TRUNC) is in effect.
ACTION Make sure that both the component's length and the
full pathname length do not exceed the {NAME_MAX} or
{PATH_MAX} limits.
ENOENT CAUSE A component of the path prefix does not exists, or
the path argument points to an empty string.
ACTION Specify a valid pathname.
ENOSPC CAUSE The directory that would contain the new file cannot
be extended, or the file system is out of file
allocation resources.
ACTION Extend accounting limits for the directory in which
the file is located, or fr ee up disk space.
ENOTDIR CAUSE A component of the path prefix is not a directory.
ACTION Specify a valid pathname.
EROFS CAUSE The named file resided on a read-only file system.
ACTION Create the slink on a writable volume (file system).
See Also
chmod(), exec(), pipe(), stat(), <sys/stat.h>, umask(), POSIX.1