Second part of sf# 1752225: On windows, emulate ftruncate with Win32
api functions. Code from fileobject.c, patch by Amaury Forgeot d'Arc.

This patch also changes:

The return value of the native ftruncate function is checked for '!=
0' instead of '< 0' as before.

fileio_seekable returns bool now instead of an int.
1 file changed