Description:
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pack() and unpack() are very useful functions, but would be nice to have a machine 
independent support for signed numbers, especially signed 32-bit little endian. If 
there are code alread for this, then they only missing from the documentation.

Test script:
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// Let's say, "E" would mean 32-bit signed little endian

echo unpack("E","A\xE2\x82\xAC")[1]."\n"; //PHP 5.4 syntax, would give back always -1400708543, regardless of architecture endianness (same az "l" on little endian system).

echo pack("E",-1400708543)."\n"; //would give back A€ on a UTF-8 terminal, same as "l" on a little endian system

Expected result:
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-1400708543
A€


Actual result:
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unknown format code