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mkdir — make directories
mkdir [−p] [−m mode] dir...
utility shall create the directories specified by the operands,
in the order specified.
For each dir
operand, the mkdir
utility shall perform actions
equivalent to the mkdir
() function defined in the System Interfaces
volume of POSIX.1‐2008, called with the following arguments:
- The dir operand is used as the path
- The value of the bitwise-inclusive OR of S_IRWXU, S_IRWXG,
and S_IRWXO is used as the mode argument. (If the −m
option is specified, the value of the mkdir() mode argument
is unspecified, but the directory shall at no time have permissions less
restrictive than the −m mode option-argument.)
utility shall conform to the Base Definitions volume of
POSIX.1‐2008, Section 12.2
, Utility Syntax Guidelines
The following options shall be supported:
- −m mode
- Set the file permission bits of the newly-created directory
to the specified mode value. The mode option-argument shall
be the same as the mode operand defined for the chmod
utility. In the symbolic_mode strings, the op characters
'+' and '−' shall be interpreted relative to an
assumed initial mode of a=rwx; '+' shall add
permissions to the default mode, '−' shall delete
permissions from the default mode.
- Create any missing intermediate pathname components.
For each dir
operand that does not name an existing directory, before
performing the actions described in the DESCRIPTION above, the mkdir
utility shall create any pathname components of the path prefix of dir
that do not name an existing directory by performing actions equivalent to
first calling the mkdir
() function with the following arguments:
- A pathname naming the missing pathname component, ending
with a trailing <slash> character, as the path argument
- The value zero as the mode argument
and then calling the chmod
() function with the following arguments:
- The same path argument as in the mkdir()
- The value
(S_IWUSR|S_IXUSR|~filemask)&0777 as the mode
argument, where filemask is the file mode creation mask of the
process (see the System Interfaces volume of POSIX.1‐2008,
operand that names an existing directory shall be ignored
The following operand shall be supported:
- A pathname of a directory to be created.
The following environment variables shall affect the execution of mkdir
- Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions volume of
POSIX.1‐2008, Section 8.2, Internationalization
Variables for the precedence of internationalization variables used to
determine the values of locale categories.)
- If set to a non-empty string value, override the values of
all the other internationalization variables.
- Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte as opposed to
multi-byte characters in arguments).
Determine the locale that should be used to affect the format and contents
of diagnostic messages written to standard error.
- Determine the location of message catalogs for the
processing of LC_MESSAGES.
The standard error shall be used only for diagnostic messages.
The following exit values shall be returned:
- All the specified directories were created successfully or
the −p option was specified and all the specified
directories now exist.
- An error occurred.
The following sections are informative.
The default file mode for directories is a
(777 on most
systems) with selected permissions removed in accordance with the file mode
creation mask. For intermediate pathname components created by mkdir
the mode is the default modified by u
so that the
subdirectories can always be created regardless of the file mode creation
mask; if different ultimate permissions are desired for the intermediate
directories, they can be changed afterwards with chmod
Note that some of the requested directories may have been created even if an
The System V −m
option was included to control the file mode.
The System V −p
option was included to create any needed
intermediate directories and to complement the functionality provided by
for removing directories in the path prefix as they become empty.
Because no error is produced if any path component already exists, the
option is also useful to ensure that a particular directory
The functionality of mkdir
is described substantially through a reference
to the mkdir
() function in the System Interfaces volume of
POSIX.1‐2008. For example, by default, the mode of the directory is
affected by the file mode creation mask in accordance with the specified
behavior of the mkdir
() function. In this way, there is less
duplication of effort required for describing details of the directory
The Base Definitions volume of POSIX.1‐2008, Chapter 8
, Section 12.2
, Utility Syntax
The System Interfaces volume of POSIX.1‐2008, mkdir()
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2013 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
7, Copyright (C) 2013 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013
Technical Corrigendum 1 applied.) In the event of any discrepancy between this
version and the original IEEE and The Open Group Standard, the original IEEE
and The Open Group Standard is the referee document. The original Standard can
be obtained online at http://www.unix.org/online.html .
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