MKDIR(2) System Calls MKDIR(2)
NAME
mkdir, mkdirat - make a directory
SYNOPSIS
#include <sys/types.h>
#include <sys/stat.h>
int mkdir(
const char *path,
mode_t mode);
int mkdirat(
int fd,
const char *path,
mode_t mode);
DESCRIPTION
The
mkdir() and
mkdirat() functions create a new directory named by the
path name pointed to by
path. The mode of the new directory is
initialized from
mode (see
chmod(2) for values of mode). The protection
part of the
mode argument is modified by the process's file creation mask
(see
umask(2)).
The directory's owner
ID is set to the process's effective user ID. The
directory's group
ID is set to the process's effective group ID, or if
the
S_ISGID bit is set in the parent directory, then the group
ID of the
directory is inherited from the parent. The
S_ISGID bit of the new
directory is inherited from the parent directory.
If
path names a symbolic link,
mkdir() and
mkdirat() fail and set errno
to
EEXIST.
The newly created directory is empty with the exception of entries for
itself (
.) and its parent directory (
..).
The
mkdirat() function behaves similarly to
mkdir(); however, if
path is
a relative path, then the directory represented by
fd is used as the
starting point for resolving
path. To use the processes current working
directory,
fd may be set to the value
AT_FDCWD.
Upon successful completion,
mkdir() and
mkdirat() mark for update the
st_atime,
st_ctime and
st_mtime fields of the directory. 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, no
directory is created, and
errno is set to indicate the error.
ERRORS
The
mkdir() and
mkdirat() functions will fail if:
EACCES Either a component of the path prefix denies search
permission or write permission is denied on the parent
directory of the directory to be created.
EDQUOT The directory where the new file entry is being placed
cannot be extended because the user's quota of disk
blocks on that file system has been exhausted; the new
directory cannot be created because the user's quota of
disk blocks on that file system has been exhausted; or
the user's quota of inodes on the file system where the
file is being created has been exhausted.
EEXIST The named file already exists.
EFAULT The
path argument points to an illegal address.
EINVAL An attempt was made to create an extended attribute that
is a directory.
EIO An I/O error has occurred while accessing the file
system.
EILSEQ The path argument includes non-UTF8 characters and the
file system accepts only file names where all characters
are part of the UTF-8 character codeset.
ELOOP Too many symbolic links were encountered in translating
path, or a loop exists in symbolic links encountered
during resolution of
path EMLINK The maximum number of links to the parent directory would
be exceeded.
ENAMETOOLONG The length of the
path argument exceeds
PATH_MAX, or the
length of a
path component exceeds
NAME_MAX while
_POSIX_NO_TRUNC is in effect.
ENOENT A component of the path prefix does not exist or is a
null pathname.
ENOLINK The
path argument points to a remote machine and the link
to that machine is no longer active.
ENOSPC No free space is available on the device containing the
directory.
ENOTDIR A component of the path prefix is not a directory. For
linkat(), if
path is a relative path and
fd refers to a
valid file descriptor which is not a directory.
EROFS The path prefix resides on a read-only file system.
The
mkdirat() function will fail if:
EBADF The path
path is a relative path and
fd is not a valid
open file descriptor or the value
AT_FDCWD.
The
mkdir() function may fail if:
ENAMETOOLONG As a result of encountering a symbolic link in resolution
of the
path argument, the length of the substituted
pathname string exceeded {
PATH_MAX}.
EXAMPLES
Example 1: Create a directory.
The following example demonstrates how to create a directory named
/home/cnd/mod1, with read, write, and search permissions for owner and
group, and with read and search permissions for others.
#include <sys/types.h>
#include <sys/stat.h>
int status;
...
status = mkdir("/home/cnd/mod1",
S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------+
|Interface Stability | Standard |
+--------------------+-------------------+
|MT-Level | Async-Signal-Safe |
+--------------------+-------------------+
SEE ALSO
chmod(2),
mknod(2),
umask(2),
mkdirp(3GEN),
stat.h(3HEAD),
attributes(7),
standards(7) September 24, 2016
MKDIR(2)