strncasecmp and strcasecmp are in strings.h rather than string.h

[Michael Wood-Vasey]

strncasecmp and strcasecmp are in "strings.h" instead of "string.h" for Mac OS X. According to the BSD/MacOSX docs, this is the POSIX standard:

​http://developer.apple.com/DOCUMENTATION/Darwin/Reference/ManPages/man3/strncasecmp.3.html

"""
HISTORY

The strcasecmp() and strncasecmp() functions first appeared in 4.4BSD.
Their prototypes existed previously in <string.h> before they were moved
to <strings.h> for IEEE Std 1003.1-2001 (POSIX.1) compliance.

BSD June 9, 1993 BSD
"""

Adding

#include<strings.h>

to

psLib/src/math/psUnaryOp.c
psLib/src/math/psBinaryOp.c

addresses this issue and allows psLib to compile on Mac OS X.

[Michael Wood-Vasey]

Later on I also needed to add fix

#include <strings.h>

to

psModules/src/objects/pmSource.c

[Michael Wood-Vasey]

This issue is included in Bug ID # 1059.

The comments in this thread of #1060 clarify that it's an issue of conforming to POSIX.