List of POSIX commands

This is a list of the shellcommands of the most recent version of the Portable Operating System Interface (POSIX) – IEEE Std 1003.1-2024 which is part of the Single UNIX Specification (SUS). These commands are implemented in many shells on modern Unix, Unix-like and other operating systems. This list does not cover commands for all versions of Unix and Unix-like shells nor other versions of POSIX.

As is typical in the context of a POSIX system, the term file refers to an item of a file system which can be a regular file, a directory or several other more specialized types.

Columns:

Command

The text one enters to launch the command.

Category

Functional categorization.

Optionality

Indicates whether the command is mandatory or optional in order to achieve conformance. If the latter, then a code indicates the optional functionality group to which the command belongs.

Batch environment (BE)

Batch job control.

C‑language development (CD)

For developing software in C.

FORTRAN development (FD)

For developing software in FORTRAN.

FORTRAN runtime (FR)

Runtime‑support for FORTRAN.

Software development (SD)

For developing software; not language specific.

User portability (UP)

Addresses consistency at the user interface level.

X/Open System Interfaces (XSI)

Historically UNIX-like features that were common on System V–style systems.

Description

Describes what the command does.

First appeared

Identifies an operating system version in which the command was first provided.