Read two files simultaneously and create one from them - bash

Question

I am new to Bash scripting, but do understand most of the basics. My scenario is as follows:
I have a server from which I get a load of data via cURL. This is parsed properly (XML format) and from these results I then extract the data I want. The cURL statement writes its output to a file called temp-rec-schedule.txt. The below code is what I use to get the values I want to use in further calculation.
MP=`cat temp-rec-schedule.txt | grep "<ns3:mediapackage" | awk -F' ' '{print $3}' | cut -d '=' -f 2 | awk -F\" '{print $(NF-1)}'`
REC_TIME=`cat temp-rec-schedule.txt | grep "<ns3:mediapackage" | awk -F' ' '{print $2}' | cut -d '=' -f 2 | awk -F\" '{print $(NF-1)}'`
So this all still work perfectly. The output of the above code is respectively (if written to two separate files):
MP output:
b1706f0d-2cf1-4fd6-ab60-ae4d08608f1f
fd578fcc-342c-4f6c-986a-794ccb1abd0c
ce9f40e9-8e2c-4654-ba1c-7f79d35a69fd
c31a2354-6f4b-4bfe-b51e-2bac80889897
df342d88-c660-490e-9da6-9c91a7966536
49083f88-4264-4629-80fb-fae480d0bb25
946121c7-4948-4254-9cb5-2457e1b99685
f7bd0cad-e8f5-4e3d-a219-650d07a4bb34
REC_TIME output:
2014-09-15T07:30:00Z
2014-09-19T08:58:00Z
2014-09-22T07:30:00Z
2014-10-13T07:30:00Z
2014-10-17T08:58:00Z
2014-10-20T07:30:00Z
2014-10-22T13:28:00Z
2014-10-27T07:30:00Z
What I want to do now is create a file where line1 from file1 is appended with line1 from file2. i.e. :
b1706f0d-2cf1-4fd6-ab60-ae4d08608f1f 2014-09-15T07:30:00Z
fd578fcc-342c-4f6c-986a-794ccb1abd0c 2014-09-19T08:58:00Z
and so on.
I am not really familiar with Perl, but do know a little bit about Bash, so if it is possible, I would like to do this in Bash.
Further, from here, I want to compare two files that contain the same MP variable, but have two different TIME values assigned: subtract the one value from the other, and calculate the amount of hours that have passed between. This is all to calculate the amount of hours that have passed between publishing a video on our system, and the start time of the recording. Basically:
File1's output: b1706f0d-2cf1-4fd6-ab60-ae4d08608f1f 2014-09-15T07:30:00Z
File2's output: b1706f0d-2cf1-4fd6-ab60-ae4d08608f1f 2014-09-15T09:30:00Z
The output of my script should yield a value of 2 hours.
How can I do this with Bash?

Answer 1

You're probably better off just using awk for the whole thing. Something like:
awk '/<ns3:medipacakge/{gsub("\"","");
split($3,mp,"=");
split($2,rt,"="); print mp[2],rt[2]}' temp-rec-schedule.txt

Answer 2

The answer to the first question is to write the output to two different files and then use paste.
grep "<ns3:mediapackage" temp-rec-schedule.txt | awk -F' ' '{print $3}' | cut -d '=' -f 2 | awk -F\" '{print $(NF-1)}' > MP_out.txt
grep "<ns3:mediapackage" temp-rec-schedule.txt | awk -F' ' '{print $2}' | cut -d '=' -f 2 | awk -F\" '{print $(NF-1)}' > REC_out.txt
paste MP_out.txt REC_out.txt
That being said (and as #WilliamPursell says in his comment on the OP) there is never a reason to string this series of commands together since awk can do all the things you are doing there with significantly less overhead and more flexibility.