sed edit file in place
On a system where sed does not have the ability to edit files in place, I think the better solution would be to use perl:
perl -pi -e 's/foo/bar/g' file.txtAlthough this does create a temporary file, it replaces the original because an empty in place suffix/extension has been supplied.
Note that on OS X you might get strange errors like "invalid command code" or other strange errors when running this command. To fix this issue try
sed -i '' -e "s/STRING_TO_REPLACE/STRING_TO_REPLACE_IT/g" <file>This is because on the OSX version of sed, the -i option expects an extension argument so your command is actually parsed as the extension argument and the file path is interpreted as the command code. Source: https://stackoverflow.com/a/19457213