I'm new to shell scripting and Terminal usage.
I have the follow line of code in a zsh script, where the PATH_VAR
is always an absolute folder path that I have to insert:
#!/bin/zsh
...
read PATH_VAR
sed -i "" "s/\"PATH_VAR=.*\"/\"PATH_VAR=$PATH_VAR\"/" file.txt
...
The idea is to replace the variable value on a text file, where the string I want to replace is ("" included):
"PATH_VAR=/Path/to/folder"
I set the variable as, for example, /Path/to/folder
; the follow line pops out:
sed: line: "s/\"PATH_VAR=.*\"/\"P ...": bad flag in substitute command: 'P'
I understand that this is due to the /
that gets interpreted differently by sed
; in fact when I run:
sed -i "" "s/\"PATH_VAR=.*\"/\"PATH_VAR=\/Path\/to\/folder\"/" file.txt
everything goes smoothly and the string gets replaced.
I want to know if there's a workaround. Since the PATH_VAR
is always an absolute path, I thought about recoursively adding the \ before every / that is found in the PATH_VAR
variable. Is this possible with sed
?
CodePudding user response:
Instead of struggling to escape those slashes, you may want to pick another separator for sed's s
command. E.g. sed 's@....@...@'
or sed 's#...#...#'
But of course, this only works if the picked separator doesn't appear in your pattern/replacement.
CodePudding user response:
Nobody ever remembers that sed
has commands besides s
. It also has, for example, c
to change a matching line:
sed -i '' '/"PATH_VAR=.*"/c\
"PATH_VAR='"$PATH_VAR"'"
' file.txt
Your variable just needs to not have any newlines in it with this approach.