MKDIR(1P)

💖 MKDIR(1P) — the POSIX Programmer's Manual, bestie edition 💖

okay so. hi. welcome to the POSIX Programmer's Manual entry for mkdir, and lemme just say upfront, no cap: this is the POSIX spec, not necessarily your Linux box. The Linux implementation of this interface may differ (so like, go check the corresponding Linux manual page for the actual Linux tea ☕), or honestly the interface might not even be implemented on Linux at all. ikyk.

---

🫶 PROLOG

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

bestie this is the vibe check warning: spec ≠ your machine. always double-check. 💅

---

✨ NAME ✨

mkdir — make directories

like. that's it. that's the whole job. it makes folders. iconic behavior honestly. 🌸

---

🎀 SYNOPSIS 🎀

mkdir [-p] [-m mode] dir...

look at her. three little pieces. we love a simple queen. 👑

---

💫 DESCRIPTION 💫

The mkdir utility shall create the directories specified by the operands, in the order specified. order matters, bestie, don't come for me.

For each dir operand, mkdir shall do stuff equivalent to the mkdir() function from the System Interfaces volume of POSIX.1‐2017, called with these arguments:

1. The dir operand is used as the path argument.
2. The value of the bitwise-inclusive OR of S_IRWXU, S_IRWXG, and S_IRWXO is used as the mode argument. (And okay, plot twist: 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. so like, never looser than what you asked for. got it? 🫡)

---

🌈 OPTIONS 🌈

The mkdir utility shall conform to the Base Definitions volume of POSIX.1‐2017, Section 12.2, Utility Syntax Guidelines. (yes queen, follow the 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. And here's the part where you gotta pay attention, fr fr: 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. so + adds, - removes, starting from a=rwx. simple as. ✨
• -p — 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:

1. A pathname naming the missing pathname component, ending with a trailing <slash> character, as the path argument
2. The value zero as the mode argument

and then calling the chmod() function with the following arguments:

1. The same path argument as in the mkdir() call
2. 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.1‐2017, umask())

Each dir operand that names an existing directory shall be ignored without error. no drama, no error message, we just move on. 💅

---

🦋 OPERANDS 🦋

The following operand shall be supported:

• dir — A pathname of a directory to be created.

---

🌸 STDIN 🌸

Not used.

(it's giving "leave me alone, I don't read from stdin") 🙈

---

🍓 INPUT FILES 🍓

None.

---

💜 ENVIRONMENT VARIABLES 💜

The following environment variables shall affect the execution of mkdir:

• LANG — Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of POSIX.1‐2017, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.)
• LC_ALL — If set to a non-empty string value, override the values of all the other internationalization variables. she's the main character, she overrides everyone. 👑
• LC_CTYPE — 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).
• LC_MESSAGES — Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.
• NLSPATH — Determine the location of message catalogs for the processing of LC_MESSAGES.

---

⚡ ASYNCHRONOUS EVENTS ⚡

Default.

---

⭐ STDOUT ⭐

Not used.

---

💀 STDERR 💀

The standard error shall be used only for diagnostic messages. that's her only job. respect it.

---

🧚 OUTPUT FILES 🧚

None.

---

🎀 EXTENDED DESCRIPTION 🎀

None.

(it's a short one bestie, we're not doing a whole essay here)

---

🔥 EXIT STATUS 🔥

The following exit values shall be returned:

• 0 — All the specified directories were created successfully, or the -p option was specified and all the specified directories either already existed or were created successfully. (slay, everything worked 🌈)
• >0 — An error occurred. (😭)

---

💅 CONSEQUENCES OF ERRORS 💅

Default.

The following sections are informative. (translation: they're the bonus content, not the requirements ✨)

---

🌈 APPLICATION USAGE 🌈

The default file mode for directories is a=rwx (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+wx 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 error occurs. so like. even when it goes wrong, it might've half-worked. check before you retry, bestie. 🙈

---

⭐ EXAMPLES ⭐

None.

---

🧠 RATIONALE 🧠

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 rmdir for removing directories in the path prefix as they become empty. Because no error is produced if any path component already exists, the -p option is also useful to ensure that a particular directory exists.

The functionality of mkdir is described substantially through a reference to the mkdir() function in the System Interfaces volume of POSIX.1‐2017. 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 creation.

(they really said "why write it twice when we can just point at mkdir()" and honestly? valid. 💅)

---

🔮 FUTURE DIRECTIONS 🔮

None.

---

👀 SEE ALSO 👀

chmod, rm, rmdir, umask

The Base Definitions volume of POSIX.1‐2017, Chapter 8, Environment Variables, Section 12.2, Utility Syntax Guidelines

The System Interfaces volume of POSIX.1‐2017, mkdir(), umask()

---

📜 COPYRIGHT 📜

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

---

and that's the whole page, bestie 🫶 go forth and make your directories, you absolute icon. this was IEEE / The Open Group, 2017, MKDIR(1P) — tysm for reading, mwah 💖