Shell Programming and Scripting

Hi Guys,

I have some basic unix knowlege but new to shell scripting. I want to replace variable values in all files in sub-directories. Any sugestion will be helpful.

Example.

Main Dir: X
Sub Dir: X1, X2, X3, X4, X5, X6.... X10
Each sub directory has file which contains variable A = 10.

I want to change value to 20 and this value should be replaced in all files in sub directories (X1.. X10)

Thanks

there is always a better way,

Code:

# !/usr/bin/ksh

for file in `find . -name '*' | xargs grep -il 'A = 10'`
do
sed -e 's/A = 10/A = 20/g' $file > temp
mv temp $file
echo "File $file done"
done

exit 0

just a quick point on matrix's script ... the files with the variables being replaced are most likely executable scripts --- you might not want to use "mv temp $file" as that would change the permissions on $file to the default permissions on temp which means most likely 644 ... use "cat temp > $file" instead ...

Code:

#! /usr/bin/ksh

for file in `find . -name '*' | xargs grep -il 'A = 10'`
do
sed -e 's/A = 10/A = 20/g' $file > temp
cat temp > $file
rm temp
echo "File $file done"
done

exit 0

btw, unless you're scripting in csh/tcsh --- there should be no spaces in between the variable name, the equal sign, and the variable value (i.e., A=10 instead of A = 10) ...

All the below 3 lines in the above 2 codes

sed -e 's/A = 10/A = 20/g' $file > temp
cat temp > $file
rm temp

can be replaced by
perl -pi -e 's/A = 10/A = 20/g' $file
## No hassle to create temp file, rename, move, or cat and redirect