Using Solaris 8.
I need to create a shell script that will edit a text file.
I need to look in the text file and do a search and replace. For instance, the text file name is always 'filename'. I need to open filename and replace every instance of 'oldtext' with 'newtext'. 'oldtext' is static. newtext is a variable that I will pass to the shell via the 'read' command further up in the script.
I've got most of the script written....I can pass the variables and create directorys, copy files etc, but I don't know how to edit a text file in a shell.

Thanks,

I figured it out. I was thinking I had to open it in vi and then do the search and replace in there - but I figured out what sed was and just put that in the script.
sed "/s/oldtext/newtext/g" filename > newfilename

Try this which is appropriate if you want to read in values from a shell variable all the time

cat oldfile | sed -e "s/testpattern/$REPL/g" > newfile

Or else, if you have perl
perl -p -i -e 's/oldtext/newtext/' <filename>
would change the file <filename> without creating a new file