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# 1  
Old 03-12-2002
sed syntax

Hi,

How can i use sed command to modify a part of a variable containing "/" by another containing "/" like describe below:

VAR="/app/share/eai"
VAR1="/app/share"
VAR2="/data/test"

echo $VAR | sed 's/... ??? # using sed to replace $VAR1 in $VAR by $VAR2 ?
# 2  
Old 03-12-2002
Try to redifine your variables with backslashes in front of your forward slashes:

VAR='\/app\/share\/eai'
VAR1='\/app\/share'
VAR2='\/data\/test'

sed -e "s/$VAR1/$VAR2/" $VAR > newfile

The forward slashes will be taken litterally by sed, unless they are escaped by the backslash character.
# 3  
Old 03-12-2002
echo $VAR | sed "s=${VAR1}=${VAR2}="
# 4  
Old 03-14-2002
MySQL

Thanks for reply.

VAR1 and VAR2 are called as arguments so i have prefered this solution:
VAR="/app/share/eai"
VAR=$(echo $VAR | sed s/\/\\\//)

VAR1=$1 # VAR1="/app/share"
VAR1=$(echo $VAR1 | sed s/\/\\\//)

VAR2=$2 # VAR2="/data/test"
VAR2=$(echo $VAR2 | sed s/\/\\\//)

echo $VAR | sed s/$VAR1/$VAR2/
# 5  
Old 03-14-2002
Whatever solution you choose - for ease of use (as was highlighted in Perderabo's reply) instead of all those //\\/\/\/\/\\\//\/\/\/\///\\\/// slahses going on...you can just use '=' as a separator for the sed fields...i.e.

sed s=/first/dir/file=second/dir/file=g

Much easier to follow....and it's not restricted to '=' ..there are others like # you can use as well........
 

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