Shell Programming and Scripting

So I'm stumped.
First... APOLOGIES... my work is offline in an office that has zero internet connectivity, as required by our client. If need be, I could print out my script attempts and retype them here. But on the off chance... here goes.

I have a text file (file_source) of terms, each line could have one, two or more words in this file.
I want to use each line from file_source as a key to grep for in a different file, (file_target)
I want to run a script that reads file_source, and uses the words from each line, to search/grep in file_target.
IE: grep "one first word" file_target, or just grep "second" file_target, etc.

In my first attempted script I have run a=`cat file_source`, then in a do loop, tried to grep "$a" file_another.
But instead of looking for all the words in one line, the routine I've created looks for each word individually from the line it's reading.
So instead of grep "a b c" file, I got grep a file, grep b file, grep c file.
Which is great... but sometimes, I really need to know that a, b and c occurred as a phrase.

I've tried multiple ideas, from cat, to read, to while to screaming. (OK, screaming is not a function, just a reaction.)
I can get a while read routine to read the whole line of file_source, but then trying to use the line to grep for in file_target fails wonderfully, saying something to the effect of source not found or what not.

I've run the script in the directory of the file I want to look at, calling out the file, and also run it pointing to the full path/file, to no avail.

If anyone has quick suggestions, outlines, ideas, or examples, WITHOUT burning up too much of your time, I'd appreciate it.
Thank you.

Bruce

You had the example

Code:

grep "one first word" file_target

This is different from

Code:

grep one first word file_target

where it searches the word "one" in the files "first", "word", "file_target".
So ensure you have the quotes, even if you have a variable line from a while read line

Code:

grep "$line" file_target

This is not advisable for several reasons: first - as you noticed - field splitting will occur and may bite you in the behind. Second, there is a much easier way to do this, see below.

Not seeing your script i can only speculate but probably the problem was quoting (or, rather, the lack thereof). You probably did:

Code:

while read line ; do
     grep $line /some/file
done < /some/file_with_phrases

Notice that you always ALWAYS have to protect your variables - you don't go outside naked, they shouldn't be made to go outside unquoted. Do it like:

Code:

while read line ; do
     grep "$line" /some/file
done < /some/file_with_phrases

But there is a much better way and it doesn't even involve a script - TADAAAAHHHH:

Well, sometimes, when the time is right, i can make a little room in my busy schedule which is filled with coming up with witty formulations for heightening the suspense and avoiding to lead to a premature climax of this most interesting topic ......*)

...to come up with a single command that does it all: grep!

Do it like this:

Code:

grep -f /some/file_with/phrases /file/to/grep/in

and grep will read the file_with_phrases, line by line, then do a search in the other file for that line. Sounds like this is what you wanted, no? To find out more about how to use grep i suggest to peruse the man page. If you still have questions, you'll be welcome.

I hope this helps.

bakunin
__________
*) You might not believe it but i can prolong that for a nearly indefinite time.

I was trying to be careful... but will double check MadeInGermay.... Thanks.

------ Post updated at 03:36 PM ------

hey Bakunin...
A - Are you sure I don't run around out there nak.... oh never mind.
And yes, it worked... the suspense got me.

ARE YOU KIDDING ME? Crap on a crapsicle stick! Grep -f....

Thank you for your time, oh wise and humorous one.

Bruce