Tribblix: manual page: mkdir.2

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