This change makes libgcal compile and run fine under OS X (which AFAIK uses FreeBSD libc).
This change makes libgcal compile and run fine under OS X (which AFAIK
uses FreeBSD libc).

Since strnlen is a GNU extension, it will not available in other *nixes.

mback2k/libgcal,Adenilson/libgcal,Adenilson/libgcal