Commands Reference, Volume 3

mkdir Command

Purpose

Creates one or more new directories.

Syntax

mkdir [ -m Mode ] [ -p ] Directory ...

Description

The mkdir command creates one or more new directories specified by the Directory parameter. Each new directory contains the standard entries . (dot) and .. (dot-dot). You can specify the permissions for the new directories with the -m Mode flag. You can use the umask subroutine to set the default mode for the mkdir command.

The owner-ID and group-ID of the new directories are set to the process's effective user-ID and group-ID, respectively. The setgid bit setting is inherited from the parent directory. To change the setgid bit, you can either specify the -m Mode flag or issue the chmod command after the creation of the directory.

Note: To make a new directory you must have write permission in the parent directory.

Flags

-m Mode

Sets the permission bits for the newly-created directories to the value specified by the Mode variable. The Mode variable takes the same values as the Mode parameter for the chmod command, either in symbolic or numeric form.

When you specify the -m flag using symbolic format, the op characters + (plus) and - (minus) are interpreted relative to the assumed permission setting a=rwx. The + adds permissions to the default mode, and the - deletes permissions from the default mode. Refer to the chmodcommand for a complete description of permission bits and formats.

-p

Creates missing intermediate path name directories. If the -p flag is not specified, the parent directory of each-newly created directory must already exist.

Intermediate directories are created through the automatic invocation of the following mkdir commands:

mkdir -p -m $(umask -S),u+wx $(dirname Directory) &&
mkdir [-m Mode] Directory

where the [-m Mode] represents any option supplied with your original invocation of the mkdir command.

The mkdir command ignores any Directory parameter that names an existing directory. No error is issued.

Exit Status

This command returns the following exit values:

0	All the specified directories were created successfully, or the -p option was specified and all the specified directories now exist.
>0	An error occurred.

Examples

To create a new directory called Test in the current working directory, enter:
```
mkdir Test
```
The Test directory is created with default permissions.
To create a new directory called Test with rwxr-xr-x permissions in the previously created /home/demo/sub1 directory, enter:
```
mkdir -m 755 /home/demo/sub1/Test
```
To create a new directory called Test with default permissions in the /home/demo/sub2 directory, enter:
```
mkdir -p /home/demo/sub2/Test
```
The -p flag creates the /home, /home/demo, and /home/demo/sub2 directories if they do not already exist.

Files

/usr/bin/mkdir

Contains the mkdir command.

Related Information

The chmod command, rm command.

The mkdir subroutine, umask subroutine.

Directory Overview in AIX 5L Version 5.2 System User's Guide: Operating System and Devices.

File and Directory Access Modes in the AIX 5L Version 5.2 System User's Guide: Operating System and Devices introduces file ownership and permissions to access files and directories.

Shells Overview in AIX 5L Version 5.2 System User's Guide: Operating System and Devices.