UNIX for Beginners Questions & Answers

Could you please advise what is the best way to edit a file without disrupting the spaces?

For example: I have within my file the value below, wherein I wanted to change VALUE2 to VALUETEST.
The total characters on the field of VALUE2 is 15 characters.

Code:

VALUE1|VALUE2<9 spaces>|VALUE3

but when I'm trying to use the command below. It keeps on adding new spaces that exceeds 15 characters.

Code:

sed s/VALUE2/VALUETEST/ <file>

Please help.

Maybe not doable with sed.
But with awk:

Code:

awk -v field=2 -v oldval="VALUE2" -v newval="VALUETEST"  -F"|"  '$field~oldval { $field=newval } { printf "%s|%-15s|%s\n", $1, $2, $3 }' file

Something like s/VALUE2 /VALUE2AAAAA/ to not change the number of spaces.

The following is even adaptive, using the * parameter in the printf format.

Code:

awk -v field=2 -v oldval="VALUE2" -v newval="VALUETEST" 'BEGIN { FS=OFS="|" } $field~oldval { len=length($field); $field=sprintf("%-*s", len, newval) } 1' file