POSIX Programmer’s Manual is available on Linux

Modern Linux distros provide POSIX Programmer’s Manual in manpages, sections

0p

1p

, and

3p

. You can check if it works on your machine:

123	man 0p stdio.h man 1p exit man 3p open

You can consult the POSIX documentation while coding on a beach or in an airplane, without Internet connection. It is always on your fingertips.

Sections

0p

1p

, and

3p

are devoted to documentation about, respectively, header files, user commands (command line), and functions called from codes written in

language.

Note that commands and section are capitalized on POSIX manpages: subject

open

in section

3p

is documented as

OPEN(3P)

. Of course, it is wrong: commands

123	man 3P OPEN man 3P open man 3p OPEN

print diagnostics like

1	No entry for OPEN in section 3P of the manual

instead of expected manpages.

Yuriy Koblents-Mishke