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Yurij
Asked: 2018-12-15 06:37:37 +0800 CST

Use sed to replace each white space with a backslash

  • 772

Just want to escape spaces in windows filepath. I'm trying this:

echo "111  1111 "| sed -e "s/[[:space:]]/\\ /g"

that only match spaces but do not replace.

command-line sed text-processing windows-subsystem-for-linux

2 Answers

  1. Best Answer

    If you use double quotes, bash interprets \\ and outputs \ which is then again interpreted from sed together with the following space to just the space.

    So you need one more backslash:

    echo "111  1111 " | sed -e "s/[[:space:]]/\\\ /g"

    but better to use single quotes to prevent the bash interpreting:

    echo "111  1111 " | sed -e 's/[[:space:]]/\\ /g'

    Output:

    111\ \ 1111\

    Alternative method:

    If you have the file path as a variable, you can use Shell methods:

    path="111  1111 "
echo ${path// /\\ }
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  2. [[:space:]] doesn’t match just spaces but rather all whitespace characters including tabs and line breaks. If you really want that, GNU sed (like in Ubuntu) has the shorthand class \s for it:

    sed 's_\s_\\&_g'

    This substitutes every (g) whitespace character (\s, matches spaces, tabs and newlines embedded in the pattern/hold spaces) in every line with a backslash (\\) and itself – & is the whole matched pattern. I use a different delimiter because slashes and backslashes always look confusing together; s/\s/\\&/g is of course valid as well.

    If you want to replace only space characters, rather use:

    sed 's_ _\\&_g'

    Example run

    $ echo "111  1111 " | sed 's_ _\\&_g'
111\ \ 1111\

    For further reading on character classes see here on regular-expressions.info.

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