This function group exists to allow PHP programmers access to POSIX functions which are not represented by other function groups in PHP. This group also contains a few functions which are not actually defined in POSIX; these are marked where appropriate.
More information on the IEEE 1003.1 POSIX standard can be found at http://standards.ieee.org/reading/ieee/std_public/description/posix/ and at http://www.pasc.org/.
This extension is compiled into PHP by default; however, you may add the --disable-posix option to the configure line when building PHP to prevent inclusion of these functions.
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