How to escape the forward slash in a sed command [duplicate] - sed

This question already has answers here:
Using different delimiters in sed commands and range addresses
(3 answers)
Closed 1 year ago.
I'm writing a shell script with this command:
sed -e 's/OLD_ITEM/NEW_ITEM/g'
But I actually want to do something that includes a directory:
sed -e 's/FOLDER/OLD_ITEM/NEW_ITEM/g'
How do ignore the forward slash so that the entire line FOLDER/OLD_ITEM is read properly?

You don't have to use / as delimiter in sed regexps. You can use whatever character you like, as long as it doesn't appear in the regexp itself:
sed -e 's#FOLDER/OLD_ITEM#NEW_ITEM#g'
or
sed -e 's|FOLDER/OLD_ITEM|NEW_ITEM|g'

You need to escape the / as \/.
The escape (\) preceding a character tells the shell to interpret that character literally.
So use FOLDER\/OLD_ITEM

Escape it !
sed -e 's/FOLDER\/OLD_ITEM/NEW_ITEM/g'

Related

Escape backslash character in sed

I need to modify some Windows paths.
For instance,
D:\usr
to
D:\first\usr
So, I have created a variable.
$path = "first\usr"
then used the following command:
sed -i -e 's!\\usr!${path}/g;' test.txt
However, this ends up with the following:
D:\firstSr
How do I escape \u in sed?
Assuming your path variable was assigned properly (without spaces in the assignment: path='first\usr'), fixing step by step for an input file test.txt with one example path:
$ cat test.txt
D:\usr
Your original command
$ sed 's!\\usr!${path}/g;' test.txt
sed: -e expression #1, char 18: unterminated `s' command
doesn't do much, as you've mixed ! and / as the delimiter.
Fixing delimiters:
$ sed 's!\\usr!${path}!g;' test.txt
D:${path}
Now no interpolation happens at all because of the single quotes. I suspect these are just copy-paste mistakes, as you obviously got some output.
Double quotes:
$ sed "s!\\usr!${path}!g" test.txt
bash: !\\usr!${path}!g: event not found
Now this clashes with history expansion. We could escape the !, or use a different delimiter.
/ as delimiter:
$ sed "s/\\usr/${path}/g" test.txt
D:\firstSr
Now we're where the question actually started. ${path} expands to first\usr, but \u has a special meaning in GNU sed in the replacement string: it uppercases the following character, hence the S.
Even without the special meaning, \u would most likely just expand to u and the backslash would be gone.
Escaping the backslash:
$ path='first\\usr'
$ sed "s/\\usr/${path}/g" test.txt
D:\first\usr
This works.
Depending on which shell you are using, you may be able to use parameter expansion to double \ in your substitution string and prevent the \u interpretation:
path="first\usr"
sed -e "s/\\usr/${path//\\/\\\\}/g" <<< "D:\usr"
The syntax for replacing a pattern with the shell parameter expansion is ${parameter/pattern/string} (one replacement) or ${parameter//pattern/string} (replace all matches).
This substitution is not specified by POSIX, but is available in Bash.
Where it is not available, you may need to filter $path through a process:
path=$(echo "$path" | sed 's/[][\\*.%$]/\\&/g')
(N.B. I have also quoted other sed metacharacters in this filter).

sed: -e expression #1, char 23: unknown option to `s' [duplicate]

This question already has an answer here:
sed fails with "unknown option to `s'" error [closed]
(1 answer)
Closed 7 years ago.
I'm trying to use sed to update a config file using a bash script. I have a similar sed command right above this one in the script that runs fine. I can't seem to figure out why this is breaking:
sed -i.bak \
-e s/"socketPath:'https://localhost:9091'"/"socketPath:'/socket'"/g \
$WEB_CONF
Any ideas?
The quotes and double quotes are causing problems.
You are using them in view of the slashes in the string.
In sed you can use another delimiter, such as a #.
sed -e 's#socketPath:https://localhost:9091#socketPath:/socket#g' \
$WEB_CONF
Escape your slashes in the pattern or use a different delimiter like this:
sed -i.bak \
-e s%"socketPath:'https://localhost:9091'"%"socketPath:'/socket'"%g \
$WEB_CONF
I am confused looking at the delimiters you have used so you can't blame sed for goofing up. When your dataset has / in them, it is often advised to use a different delimiters like # or _ (yes, sed supports various delimiters).
Also, your quoting looks abit off. The syntax should be:
sed -i.bak 's#substitute#replacement#g' "$WEB_CONF"
If your substitute and/or replacement has variables use " instead ' which will allow it to interpolate.

Substitute with backslash in sed

I want to replace word with \word{sth} with sed.
I type in
sed -i s#word#\\word{sth}
but i am getting is word{sth} instead of \word{sth}
I tried with 1 slash also in the command
you should add four backslashes.
you need two to escape the backslash by the terminal, and two to escape it for sed. 2*2=4.
$ echo word|sed s#word#\\\\word{sth}#gi
\word{sth}
Consider enclosing sed expression with single-quotes '
sed -i 's#word#\\word{sth}#' file

How to insert strings containing slashes with sed? [duplicate]

This question already has answers here:
Using different delimiters in sed commands and range addresses
(3 answers)
Closed 1 year ago.
I have a Visual Studio project, which is developed locally. Code files have to be deployed to a remote server. The only problem is the URLs they contain, which are hard-coded.
The project contains URLs such as ?page=one. For the link to be valid on the server, it must be /page/one .
I've decided to replace all URLs in my code files with sed before deployment, but I'm stuck on slashes.
I know this is not a pretty solution, but it's simple and would save me a lot of time. The total number of strings I have to replace is fewer than 10. A total number of files which have to be checked is ~30.
An example describing my situation is below:
The command I'm using:
sed -f replace.txt < a.txt > b.txt
replace.txt which contains all the strings:
s/?page=one&/pageone/g
s/?page=two&/pagetwo/g
s/?page=three&/pagethree/g
a.txt:
?page=one&
?page=two&
?page=three&
Content of b.txt after I run my sed command:
pageone
pagetwo
pagethree
What I want b.txt to contain:
/page/one
/page/two
/page/three
The easiest way would be to use a different delimiter in your search/replace lines, e.g.:
s:?page=one&:pageone:g
You can use any character as a delimiter that's not part of either string. Or, you could escape it with a backslash:
s/\//foo/
Which would replace / with foo. You'd want to use the escaped backslash in cases where you don't know what characters might occur in the replacement strings (if they are shell variables, for example).
The s command can use any character as a delimiter; whatever character comes after the s is used. I was brought up to use a #. Like so:
s#?page=one&#/page/one#g
A very useful but lesser-known fact about sed is that the familiar s/foo/bar/ command can use any punctuation, not only slashes. A common alternative is s#foo#bar#, from which it becomes obvious how to solve your problem.
add \ before special characters:
s/\?page=one&/page\/one\//g
etc.
In a system I am developing, the string to be replaced by sed is input text from a user which is stored in a variable and passed to sed.
As noted earlier on this post, if the string contained within the sed command block contains the actual delimiter used by sed - then sed terminates on syntax error. Consider the following example:
This works:
$ VALUE=12345
$ echo "MyVar=%DEF_VALUE%" | sed -e s/%DEF_VALUE%/${VALUE}/g
MyVar=12345
This breaks:
$ VALUE=12345/6
$ echo "MyVar=%DEF_VALUE%" | sed -e s/%DEF_VALUE%/${VALUE}/g
sed: -e expression #1, char 21: unknown option to `s'
Replacing the default delimiter is not a robust solution in my case as I did not want to limit the user from entering specific characters used by sed as the delimiter (e.g. "/").
However, escaping any occurrences of the delimiter in the input string would solve the problem.
Consider the below solution of systematically escaping the delimiter character in the input string before having it parsed by sed.
Such escaping can be implemented as a replacement using sed itself, this replacement is safe even if the input string contains the delimiter - this is since the input string is not part of the sed command block:
$ VALUE=$(echo ${VALUE} | sed -e "s#/#\\\/#g")
$ echo "MyVar=%DEF_VALUE%" | sed -e s/%DEF_VALUE%/${VALUE}/g
MyVar=12345/6
I have converted this to a function to be used by various scripts:
escapeForwardSlashes() {
# Validate parameters
if [ -z "$1" ]
then
echo -e "Error - no parameter specified!"
return 1
fi
# Perform replacement
echo ${1} | sed -e "s#/#\\\/#g"
return 0
}
this line should work for your 3 examples:
sed -r 's#\?(page)=([^&]*)&#/\1/\2#g' a.txt
I used -r to save some escaping .
the line should be generic for your one, two three case. you don't have to do the sub 3 times
test with your example (a.txt):
kent$ echo "?page=one&
?page=two&
?page=three&"|sed -r 's#\?(page)=([^&]*)&#/\1/\2#g'
/page/one
/page/two
/page/three
replace.txt should be
s/?page=/\/page\//g
s/&//g
please see this article
http://netjunky.net/sed-replace-path-with-slash-separators/
Just using | instead of /
Great answer from Anonymous. \ solved my problem when I tried to escape quotes in HTML strings.
So if you use sed to return some HTML templates (on a server), use double backslash instead of single:
var htmlTemplate = "<div style=\\"color:green;\\"></div>";
A simplier alternative is using AWK as on this answer:
awk '$0="prefix"$0' file > new_file
You may use an alternative regex delimiter as a search pattern by backs lashing it:
sed '\,{some_path},d'
For the s command:
sed 's,{some_path},{other_path},'

sed windows replace string containing space

I'm trying to replace a string AUD A0-FX.20 with AUD/USD.20 using sed for windows through the windows cmd shell.
I dont think windows shell handles spaces in strings well. Here is what I'm running -
SED -e s{AUD A0-FX.20{AUD/USD.20{ "C:\sed\bin\text.txt" > "C:\sed\bin\text1.txt"
but I get an error SED: -e expression #1, char 5: unterminateds' command`
I'm using { as the delimiter because i already have a / in the replacement string. Any help would be appreciated. I'm using sed for windows from http://gnuwin32.sourceforge.net/packages/sed.htm
I don't know if this will solve your question because can't test in Windows, but I will give two suggestions:
. is special for sed and matches any character. Escape it like \.
Quote your sed instructions, with single or double quotes, like "s{...{...{"
Try:
sed "s|AUD A0-FX\.20|AUD/USD.20|"