DragonFlyBSD

Fixes an array out of bounds error in usr.bin/shlock/shlock.c. The fix reduces the offset accessed where the error occurs, but increasing the size of the local variable 'buf' to BUFSIZE + 1 would also be a valid fix.

The other changes to the other files are trivial changes to make other code more 'correct' by having it follow strict aliasing rules. As such they are not important unless the code is being compiled with -O2 or higher.