sed regex question

ShaqDiesel · 02-09-2007, 07:05 PM

I am using using the following regex string
regex="letter1.letter1.letter1" in a ksh script. The dots are supposed to be metacharacters that would match any single character.

I was hoping sed -i "s/($regex)/hello$1/g file1 would transform
"letter1 letter1 letter1" to "hello letter1 letter1 letter1" in file1 but it didn't do anything. I'd like to mention that I can't just use a literal in the substitute statement because it isn't always "letter1". What's going on here? Thanks in advance.

Tinkster · 02-09-2007, 07:24 PM

Try this:

Code:

[tink:~]$ regex="letter1.letter1.letter1"
[tink:~]$ sed "s/\($regex\)/hello\1/g" file1
helloletter1 letter1aletter1
helloletter1.letter1.letter1
letter1 letter2 letter1

where file1 looks like

Code:

$ cat file1
letter1 letter1aletter1
letter1.letter1.letter1
letter1 letter2 letter1

Cheers,
Tink