Reading code has its place and tracing code has its place. I have difficulty understanding nontrivial codebases without some amount of tracing. In this case you chose to present the source for a FreeBSD/OS X version of killall when OP is running Linux.
Reading code has its place and tracing code has its place. I have difficulty understanding nontrivial codebases without some amount of tracing. In this case you chose to present the source for a FreeBSD/OS X version of killall when OP is running Linux.