Bash脚本使用sed替换给定UNIX系统路径的字符串

Question

I have the following bash script named SetScript :

#!/bin/bash

# make sure CWD is correct location
if [ ! -f $1 ];
then
    echo "No file at \"$1\" found."
    exit 0
fi

sed -i -r "s/^([\t ]+SCRIPT = \")[^\"]*\";\ #\*/\1$2\";\ #\*/" $1

This script is used to change lines like the following in a text file:

    SCRIPT = "default.script"; #*

The text file is just a config text file that I'm using with the libconfig++ library.

So, for example, if my config text file is named settings.cfg , then I might do this

SetScript settings.cfg another.script

or even this

SetScript settings.cfg "another.script"

These commands would result in the text-file line from above being changed to:

    SCRIPT = "another.script"; #*

So far so good. However, when I try to replace with a UNIX path that includes a forward slash, I get issues with sed. For example:

$ SetScript settings.cfg "/home/me/some.script"
sed: -e expression #1, char 38: unknown option to `s'
$ SetScript settings.cfg /home/me/some.script
sed: -e expression #1, char 38: unknown option to `s'

My question, then, is: how can I modify my bash script (while still using sed ) to permit replacement by any UNIX system path (relative or full)?

Answer 1

This is because the sed separator you are using is also / , so sed command gets confused when it sees so many slashes.

Try setting another separator, for example _ :

sed -i -r "s_^([\t ]+SCRIPT = \")[^\"]*\";\ #\*_\1$2\";\ #\*_" $1
            ^                                  ^            ^

Example

$ echo "he/llo" | sed 's/he/bye/'
byello
$ echo "he/llo" | sed 's/he/llo/bye/'
sed: -e expression #1, char 10: unknown option to `s'
$ echo "he/llo" | sed 's_he/llo_bye_'
bye