UNIX for Dummies Questions & Answers

one of my colleagues has this question.
he has a command, C_CMD which accepts 4 variables, $1 $2 $3 $4
he wants to load up a file with multiple rows, one row per set of variables and then iteratively execute the command based on the content of the file.

example:
at the command line you'd issue:
C_CMD A1 B1 C1 D1
C_CMD A2 B2 C2 D2
C_CMD A3 B3 C3 D3

but he wants to have FILE_C with:
A1 B1 C1 D1
A2 B2 C2 D2
A3 B3 C3 D3

and then process this in a script to iteratively invoke C_CMD similar to how you would with a single variable like this
for $file in `cat \path\FILE_D`
do
D_CMD $file
done

can you assist? I thought I saw something similar here a few days ago but now cannot find it.

Lisa

Lisa,
You are almost there:

Code:

while read mParms
do
  D_CMD $mParms
done < \path\FILE_D

Shell_Life
I may be a little dense here - is that an answer for my multiple variable example or for my single variable example?
you used my single var "names" and that's what is confusing me.
I was asking how to script the C_CMD $1 $2 $3 $4 example
if your answer does that, please excuse my thickheadedness - I will try it when I can login again.

Lisa,
The single variable 'mParms' has all your parameters from each record
in your file.

yes, thank you - I could see that after I "slept on it"
what if I changed it up and needed to be able to reference them separately like
C_CMD $1 | grep $2 | grep -v $3 | lp -d$4

would I have to just parse them out of the one variable or is there a differen techinque to use in that case

(not that I'd write that stmt but just example of piping and passing them)

If you want to access each individual variable:

Code:

while read mVar1 mVar2 mVar3 mVar4
do
  echo "1 = "${mVar1}" 2 = "${mVar2}" 3 = "${mVar3}" 4 = "${mVar4}
done < input_file