Why is sed failing when using two variables?

Asked Mar 05 '19 at 14:32

Active Mar 05 '19 at 18:09

Viewed 167 times

sed fails with the following error:

sed: -e expression #1, char 72: unterminated `s' command

Here is my script:

#!/bin/bash
OLD="$(cat /etc/fstab | grep /tmp)"
NEW="$(cat /etc/fstab | grep /tmp | sed 's/,noexec//')"
sed "s|$OLD|$NEW|" /etc/fstab

I don't see how it is unterminated, I have 3 | symbols as delimiters and am using double quotes since I have variables in the statement.

I have read many other questions on stack overflow and other blogs that are similar, but none that were using two variables like this.

Edit to show fstab:

LABEL=/boot    /boot    xfs    defaults,nodev,nosuid,noexec    1    2
/dev/mapper/LV_tmp    /tmp    xfs    nodev,noexec    1    2
proc    /proc    proc    defaults    0    0

edited Mar 05 '19 at 14:55

asked Mar 05 '19 at 14:32

J. Tate

What is in `$OLD` and `$NEW`? Your `sed "s|$OLD|$NEW|"` command contains variables. You might not see any `/`s there, but they may be there. – Wiktor Stribiżew Mar 05 '19 at 14:34
1

Or [Is it possible to escape regex metacharacters reliably with sed](https://stackoverflow.com/questions/29613304/is-it-possible-to-escape-regex-metacharacters-reliably-with-sed) – Wiktor Stribiżew Mar 05 '19 at 14:36
There are `/`s, which is why I use `|` as a delimiter – J. Tate Mar 05 '19 at 14:46
Ok, but there may be `|`s, too. – Wiktor Stribiżew Mar 05 '19 at 14:48
There are not. It is an fstab file like the original post says. I have also tried `@` as a delimiter – J. Tate Mar 05 '19 at 14:50
Can you supply the content of your fstab or enough to reproduce as there are many versions of fstab. – Alex Harvey Mar 05 '19 at 14:51
[Not repro](https://ideone.com/GF5cOz). – Wiktor Stribiżew Mar 05 '19 at 14:59
Please run your script with `bash -x yourscript` to geta helpful debug log – that other guy Mar 05 '19 at 16:18

Why is sed failing when using two variables?

0 Answers0