sending a sigcont process causes SIGSEV

[GoogleCodeExporter]

What steps will reproduce the problem?
1. type command sleep 3
2. ctrl-z
3. continue the program by sending the process SIGCONT signal - 18

What is the expected output? What do you see instead?
It should resume the job 

What version of the product are you using? On what operating system?
Newest one, Mac OS X

Please provide any additional information below.
based on the program, it doesn't seem that you malloced the job-list. 

Original issue reported on code.google.com by JojoF...@gmail.com on 14 Apr 2015 at 9:44

Attachments:

• [Screen Shot 2015-04-14 at 5.41.06 AM.png](https://storage.googleapis.com/google-code-attachments/mini-shell/issue-2/comment-0/Screen Shot 2015-04-14 at 5.41.06 AM.png)

[GoogleCodeExporter]

killJob() calls getJob but getJob returns null since 18 does not belong in the 
list - should send an error instead of accessing null memory. 

temporary fix is to have a condition on handling a value that returns null. 

Original comment by JojoF...@gmail.com on 14 Apr 2015 at 9:52