Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


MKDIR(2) Linux Programmer's Manual MKDIR(2)


     mkdir, mkdirat - create a directory


     #include <sys/stat.h>
     #include <sys/types.h>
     int mkdir(const char *pathname, mode_t mode);
     #include <fcntl.h>           /* Definition of AT_* constants */
     #include <sys/stat.h>
     int mkdirat(int dirfd, const char *pathname, mode_t mode);
 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
         Since glibc 2.10:
             _POSIX_C_SOURCE >= 200809L
         Before glibc 2.10:


     mkdir() attempts to create a directory named pathname.
     The  argument  mode  specifies  the  mode  for  the  new directory (see
     inode(7)).  It is modified by the process's umask in the usual way:  in
     the  absence  of  a  default  ACL, the mode of the created directory is
     (mode & ~umask & 0777).  Whether other mode bits are  honored  for  the
     created  directory  depends  on  the  operating system.  For Linux, see
     NOTES below.
     The newly created directory will be owned by the effective user  ID  of
     the process.  If the directory containing the file has the set-group-ID
     bit set, or if the filesystem  is  mounted  with  BSD  group  semantics
     (mount -o bsdgroups or, synonymously mount -o grpid), the new directory
     will inherit the group ownership from its parent; otherwise it will  be
     owned by the effective group ID of the process.
     If  the parent directory has the set-group-ID bit set, then so will the
     newly created directory.
     The mkdirat() system call operates in exactly the same way as  mkdir(),
     except for the differences described here.
     If  the  pathname given in pathname is relative, then it is interpreted
     relative to the directory referred to  by  the  file  descriptor  dirfd
     (rather  than  relative to the current working directory of the calling
     process, as is done by mkdir() for a relative pathname).
     If pathname is relative and dirfd is the special value  AT_FDCWD,  then
     pathname  is  interpreted  relative to the current working directory of
     the calling process (like mkdir()).
     If pathname is absolute, then dirfd is ignored.
     See openat(2) for an explanation of the need for mkdirat().


     mkdir() and mkdirat() return  zero  on  success,  or  -1  if  an  error
     occurred (in which case, errno is set appropriately).


     EACCES The  parent  directory  does  not  allow write permission to the
            process, or one of the directories in  pathname  did  not  allow
            search permission.  (See also path_resolution(7).)
     EDQUOT The  user's quota of disk blocks or inodes on the filesystem has
            been exhausted.
     EEXIST pathname already exists (not necessarily as a directory).   This
            includes the case where pathname is a symbolic link, dangling or
     EFAULT pathname points outside your accessible address space.
     EINVAL The final component ("basename") of the new directory's pathname
            is  invalid  (e.g.,  it contains characters not permitted by the
            underlying filesystem).
     ELOOP  Too many symbolic links were encountered in resolving  pathname.
     EMLINK The  number  of  links  to  the  parent  directory  would exceed
            pathname was too long.
     ENOENT A directory component in pathname does not exist or  is  a  dan-
            gling symbolic link.
     ENOMEM Insufficient kernel memory was available.
     ENOSPC The  device  containing  pathname has no room for the new direc-
     ENOSPC The new directory cannot be  created  because  the  user's  disk
            quota is exhausted.
            A  component  used as a directory in pathname is not, in fact, a
     EPERM  The filesystem containing pathname does not support the creation
            of directories.
     EROFS  pathname refers to a file on a read-only filesystem.
     The following additional errors can occur for mkdirat():
     EBADF  dirfd is not a valid file descriptor.
            pathname is relative and dirfd is a file descriptor referring to
            a file other than a directory.


     mkdirat() was added to Linux in  kernel  2.6.16;  library  support  was
     added to glibc in version 2.4.


     mkdir(): SVr4, BSD, POSIX.1-2001, POSIX.1-2008.
     mkdirat(): POSIX.1-2008.


     Under  Linux,  apart  from the permission bits, the S_ISVTX mode bit is
     also honored.
     There are many infelicities in the protocol underlying  NFS.   Some  of
     these affect mkdir().
 Glibc notes
     On  older  kernels  where  mkdirat()  is unavailable, the glibc wrapper
     function falls back to the use of mkdir().  When pathname is a relative
     pathname,  glibc  constructs  a  pathname based on the symbolic link in
     /proc/self/fd that corresponds to the dirfd argument.


     mkdir(1), chmod(2), chown(2), mknod(2),  mount(2),  rmdir(2),  stat(2),
     umask(2), unlink(2), acl(5) path_resolution(7)


     This  page  is  part of release 4.16 of the Linux man-pages project.  A
     description of the project, information about reporting bugs,  and  the
     latest     version     of     this    page,    can    be    found    at

Linux 2017-09-15 MKDIR(2)

/data/webs/external/dokuwiki/data/pages/man/mkdirat.txt · Last modified: 2019/05/17 09:32 by

Was this page helpful?-10+1

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki