I'm completely new to bash scripting so excuse me....
I am trying to combine some html content with a template that contains standard headings, the template has a place-holder "REPLACEME" which I thought I could just find and replace on. The loop simply repeats the operation on all the files in the directory.
REPLACEME="REPLACEME"
for file in *.html
do
TEMPLATE=$(<../template/template.html)
CONTENT=$(<$file)
OUTPUT="${TEMPLATE/"$REPLACEME"/"$CONTENT"}"
echo $OUTPUT > ../compiled/$file
done
This works but the resulting html file has been stripped of new line characters, which makes it look like junk! Can anyone help?
Replace:
echo $OUTPUT > ../compiled/$file
With:
echo "$OUTPUT" > ../compiled/$file
The shell performs word splitting on unquoted variables. With the default value for IFS, this means that all sequences of whitespace, which includes tabs and newlines, are replaced with a single blank. To prevent that, put the variable in double-quotes as shown above.
Using sed you could achieve it like below :
sed -i 's/REPLACEME/new_text/g' /path/to/your/template.html
The -i option in sed is for inplace edit & the g option is for global substitution.
Edit 1:
If you need to use a variable inside sed you can do it this way
var="Sometext";
sed -i "s/REPLACEME/$var/g" /path/to/your/template.html
Mind the double quotes here, it makes the shell expand variables.
If your system supports gnu-awk (gawk) you may achieve the above with
gawk '
{
$0=gensub(/REPLACEME/"NEWTEXT","g",$0)
printf "%s\n", $0
}' < /path/to/your/template.html > newtemplate.html && mv newtemplate.html template.html
Related
The name in the title says it all. However, I'm absolutely the worst with the sed command. So I'm trying to edit the following file:
/var/www/html/phpMyAdmin/config.inc.php
I want to edit the line that says
$cfg['Servers'][$i]['AllowRoot'] = false;
into the following
$cfg['Servers'][$i]['AllowRoot'] = true;
It has so many special characters and whatnot and I have no prior knowledge of how sed works. So here's some commands I've tried to specifically edit that one line.
sed -i "/*.AllowRoot.*/\$cfg['Servers'][\$i]['AllowRoot'] = true;/" /var/www/html/phpMyAdmin/config.inc.php
sed -i "/*.AllowRoot.*/$cfg['Servers'][$i]['AllowRoot'] = true;/" /var/www/html/phpMyAdmin/config.inc.php
# this one finds the line successfully and prints it so I know it's got the right string:
sed -n '/AllowRoot/p' /var/www/html/phpMyAdmin/config.inc.php
sed -i "s/'AllowRoot|false'/'AllowRoot|true'/" /var/www/html/phpMyAdmin/config.inc.php
I have absolutely no idea what I'm doing and I'm not learning a whole lot besides the feeling that the last command splits up 'AllowRoot|false' makes sure that both must be present in the sentence to come back as a result. So to my logic, I thought changing the word false into true would make that happen, but nothing. The other commands return... bizarre results at best, one even emptying the file. Or that's one of the commands I had not written down here, I've lost track after 50 attempts. What is the solution here?
The [ and ] need to be escaped to match literal brackets, instead of inadvertently starting a bracket expression. This should work:
$ sed -i "/\$cfg\['Servers'\]\[\$i\]\['AllowRoot'\]/s/false/true/" /var/www/html/phpMyAdmin/config.inc.php
There is not many things to escape in sed. Main problem in your line is / which you have chosen as delimiter (most common, but not required). I suggest you use # and the following will work:
sed -i "s#$cfg['Servers'][$i]['AllowRoot'] = false;<br />#$cfg['Servers'][$i]['AllowRoot'] = true;<br />#g" input.txt
however you need to think about bash interpreter as well. $i and $cfg will be interpreted as variables. My suggestion is that when you want to match a string like this to put the sed expression in a text file like this:
cat allow_root_true.sed
s#['Servers'][]['AllowRoot'] = false;<br />#['Servers'][]['AllowRoot'] = true;<br />#g
and run the command using sed -f like this:
sed -i -f allow_root_true.sed input.txt
Warning -i will change the input file
sed can't do literal string matching which is why you need to escape so many characters (see Is it possible to escape regex metacharacters reliably with sed), but awk can:
$ awk -v str="\$cfg['Servers'][\$i]['AllowRoot']" 'index($0,str){sub(/false/,"true")} 1' file
//some text here
$cfg['Servers'][$i]['AllowRoot'] = true;<br />
//some more text here
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In the above we only have to escape the $s to protect them from the shell since the string is enclosed in "s to allow it to include 's.
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},'
Part of a shell script that I am creating takes a plain text list of files...
11111.jpg
22222.jpg
33333.jpg
...and appends a user-defined prefix that is stored in a variable to create a list of paths that looks like this:
user/defined/prefix/11111.jpg
user/defined/prefix/22222.jpg
user/defined/prefix/33333.jpg
I am attempting to use sed to add the prefix in this manner:
sed -e 's/^/prefix/' oldFile > newFile.new
The variable is getting assigned correctly:
echo $selectedPrefix
user/defined/prefix
Put no combinations of single quotes, double quotes of whatever seem to get sed to use the ACTUAL value of the variable instead of just the variable name.
sed -e 's/^/$selectedPrefix/' oldFile > newFile.new
Yields:
$selectedPrefix11111.jpg
$selectedPrefix22222.jpg
$selectedPrefix33333.jpg
Help! I'm sure the solution is simple but I feel like I've tried everything....
As mentionned by Cyrus, you need to used " (double quote) instead ' (single quote) if you want the variable replacement because single quoted string are interpreted literally so it doesn't see $selectedPrefix as a variable but as the string value of $selectedPrefic hence what you saw.
Since you are working with paths in you sed, you are correct in assuming that you should use a different separator for your sed comment. I usually prefer using | but ~ would also work.
so basically you could have:
sed -e "s~^~$selectedPrefix~" oldFile > newFile.new
This code would solve your problem:
selectedPrefixEscaped="$(echo "$selectedPrefix" | sed 's/\//\\\//g')" && sed -e "s/^/$selectedPrefixEscaped/" oldFile > newFile.new
Just using a different delimiter on sed would leave you open to problems when (if) the path contains the new delimiter (ex.: /folder/folder#5/file.txt would be problematic if using # as sed delimiter).
I am trying to remove all of the matches of $word from a file, but only on lines where $word is placed somewhere within { and } which also appear on the same line, e.g.:
{The cat liked} the fish.
The mouse {did not like} the cat.
The {cat did not} like the spider.
If $word is set to "cat", then lines 1 and 3 are deleted, because "cat" appears between the { and }. If $word is set to "like", then lines 1 and 2 are deleted, because this search term appears on those lines between the { and }. Line 3 is not deleted, because like appears outside of the braces.
The braces are never nested.
The braces never appear split across lines.
I have tried various things, but these all returned errors:
sed -i "/\{*$word*\}/d" ./file.txt
sed -i "/\{.*$word.*\}/d" ./file.txt
sed -i "/\{(.*)$word(.*)\}/d" ./file.txt
How can I remove all of the lines in a file containing a variable, but only when the found variable was on a line and found between two braces?
sed -i "/{.*$word.*}/d" ./file.txt
\{ in sed actually have a special meaning, not the literal {, you should just write a { to represent the literal character. (which would be confusing if you are well familiar with perl regex ...)
Edit:
Be careful with -i, if this is in a script, and accidently $word is not defined or set to empty string, this command will delete all lines containing { no matter what between }.
I would take the answer that #cybeliak gave a little further. If you really want to match cat and not, say scat, then you need to delimit your expression with word boundaries:
sed '/{.*[[:<:]]'$word'[[:>:]].*}/d'
Note - I prefer to use ' ' style quotes to prevent any unintended side-effects...
As an aside, I am a big fan of not using the -i flag. Pipe the result into a different file and confirm for yourself that it's good, before deleting the original.
Much easier to do with awk:
awk -v s="cat" -F '[{}]' '!($2 ~ s)' file
The mouse {did not like} the cat.
awk -v s="like" -F '[{}]' '!($2 ~ s)' file
The {cat did not} like the spider.
This might work for you (GNU sed):
sed -i '/{[^}]*'"$word"'[^}]*}/d' file
N.B. $wordshould not contain } or /.
I have a flat file that contains something like this:
11|30646|654387|020751520
11|23861|876521|018277154
11|30645|765418|016658304
Using shell script, I would like to append a string to certain lines in this file, if those lines contain a specific string.
For example, in the above file, for lines containing 23861, I would like to append a string "Processed" at the end, so that the file becomes:
11|30646|654387|020751520
11|23861|876521|018277154|Processed
11|30645|765418|016658304
I could use sed to append the string to all lines in the file, but how do I do it for specific lines ?
I'd do it this way
sed '/\|23861\|/{s/$/|Something/;}' file
This is similar to Marcelo's answer but doesn't require extended expressions and is, I think, a little cleaner.
First, match lines having 23861 between pipes
/\|23861\|/
Then, on those lines, replace the end-of-line with the string |Something
{s/$/|Something/;}
If you want to do more than one of these you could simply list them
sed '/\|23861\|/{s/$/|Something/;};/\|30645\|/{s/$/|SomethingElse/;}' file
Use the following awk-script:
$ awk '/23861/ { $0=$0 "|Processed" } {print}' input
11|30646|654387|020751520
11|23861|876521|018277154|Processed
11|30645|765418|016658304
or, using sed:
$ sed 's/\(.*23861.*$\)/\1|Processed/' input
11|30646|654387|020751520
11|23861|876521|018277154|Processed
11|30645|765418|016658304
Use the substitution command:
sed -i~ -E 's/(\|23861\|.*)/\1|Processed/' flat.file
(Note: the -i~ performs the substitution in-place. Just leave it out if you don't want to modify the original file.)
You can use the shell
while read -r line
do
case "$line" in
*23681*) line="$line|Processed";;
esac
echo "$line"
done < file > tempo && mv tempo file
sed is just a stream version of ed, which has a similar command set but was designed to edit files in place (allegedly interactively, but you wouldn't want to use it that way unless all you had was one of these). Something like
field_2_value=23861
appended_text='|processed'
line_match_regex="^[^|]*|$field_2_value|"
ed "$file" <<EOF
g/$line_match_regex/s/$/$appended_text/
wq
EOF
should get you there.
Note that the $ in .../s/$/... is not expanded by the shell, as are $line_match_regex and $appended_text, because there's no such thing as $/ - instead it's passed through as-is to ed, which interprets it as text to substitute ($ being regex-speak for "end of line").
The syntax to do the same job in sed, should you ever want to do this to a stream rather than a file in place, is very similar except that you don't need the leading g before the regex address:
sed -e "/$line_match_regex/s/$/$appended_text/" "$input_file" >"$output_file"
You need to be sure that the values you put in field_2_value and appended_text never contain slashes, because ed's g and s commands use those for delimiters.
If they might do, and you're using bash or some other shell that allows ${name//search/replace} parameter expansion syntax, you could fix them up on the fly by substituting \/ for every / during expansion of those variables. Because bash also uses / as a substitution delimiter and also uses \ as a character escape, this ends up looking horrible:
appended_text='|n/a'
ed "$file" <<EOF
g/${line_match_regex//\//\\/}/s/$/${appended_text//\//\\/}/
wq
EOF
but it does work. Nnote that both ed and sed require a trailing / after the replacement text in s/search/replace/ while bash's ${name//search/replace} syntax doesn't.