use of system() is evil

[joej]

phook is a great idea. Consider making it more secure and compliant ...

Why system() is evil and insecure: http://www.cplusplus.com/forum/articles/11153/

Even CERT warns about its usage: https://www.securecoding.cert.org/confluence/pages/viewpage.action?pageId=2130132

[drinchev]

@joej, thanks for mentioning that.

C is not my language of specialty, so I was expecting complaints about what I wrote.

I will try to improve the code ( also I'm a bit concerned about the global after pointer - needed that for the signal handler ), but it will be great if you can have a look and suggest ( contribute ) other aspects of the super small program.

Thank you one more time!