Trying to Grep Multiple Phone Numbers Around a Specific Time
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I work in at a telecom company and in some cases I need to search for multiple numbers around a specific time. I am using Ubuntu sever 10.04. When I search for a call my normal expression is:

grep 5555551234 20120719-12*

Where  20120719-12* is the date and time (GMT) for the number I am looking for.

When I use  
grep 5555551234 20120719-18* | 5555551235 20120719-18*

I will only get a return on the first number

If I use 
grep 5555551234 | 5555551235 20120719-18*

I receive -sh 5555551235 not found

Any feedback would be appreciated..

