I have a small problem. In my original.txt file I got some scheme with one variable zmuser to change.
I'm using sed command to change my variable 'zmuser' to other string, which is also a variable.
sed -i -e s/zmuser/${user}/g original.txt
It changes the zmuser for my $user variable in original.txt.
How can I make changes from the file original.txt but save it in another .txt file?
This should do it:
sed -e "s/zmuser/${user}/g" original.txt > another.txt
How it works:
If you omit the -i flag from your sed command, the output will be printed on stdout. The > another.txt construct redirects that output to another.txt file.
you can also do
sed -n -e "s/zmuser/${user}/g" -e "w another.txt" original.txt
Related
I want to append bash variable (which has html tags) at the beginning of a file.
INSERTTO=<h2>title</h2>
<li>sdfdsf</li>
Below is the command I am using -
sed -i '1i'$INSERTTO file.html
But i am getting error -
sed: -e expression #1, char 177: unknown command: `<'
Do i need to encode the html tags in INSERTTO variable ?
First of all, use quotes:
INSERTTO='<h2>title</h2>
<li>sdfdsf</li>'
Then try this:
sed "1 i $INSERTTO" file.html
Start with some text in your file, e.g.
$ cat file
some text
Then you need your variable to contain an explicit '\n' character where the line break is, e.g. INSERTTO='<h2>title</h2>\n<li>sdfdsf</li>'. Then you can use the sed expression to place both lines as the beginning lines in the file, e.g.
$ INSERTTO='<h2>title</h2>\n<li>sdfdsf</li>'; sed "1i $INSERTTO" file
<h2>title</h2>
<li>sdfdsf</li>
some text
Now at present, what will be done has only been written to the terminal stdout. To modify the file in place, you will need to add the -i option for sed (or -i.bak to save a backup of the original file with the .bak extension. (however you prefer to do it)
I offer you an ed(1) solution.
INSERTTO=<h2>title</h2>
<li>sdfdsf</li>
printf '%s\n' 1i "$INSERTTO" . w | ed -s file.html
Assuming the file is not empty that will work. otherwise use 0a as the address and command instead of 1i
... Or use the cat(1) and mv(1)
INSERTTO=<h2>title</h2>
<li>sdfdsf</li>
Add the stdin flag and use a herestring works in bash but not in POSIX shells.
cat - file.html <<< "$INSERTTO"
You should see the output to stdout, redirect it to another file and move that file to the original file, something like this.
cat - file.html <<< "$INSERTTO" > tempfile && mv tempfile file.html
However if the html file is a symlink then it is now broken... a work around would be to use another cat.
cat - file.html <<< "$INSERTTO" > tempfile && cat tempfile > file.html && rm tempfile.
tempfile is just an example you should take a loot at How to create a tempfile in a secure manner
I have these files
NotRequired.txt (having lines which need to be remove)
Need2CleanSED.txt (big file , need to clean)
Need2CleanGRP.txt (big file , need to clean)
content:
more NotRequired.txt
[abc-xyz_pqr-pe2_123]
[lon-abc-tkt_1202]
[wat-7600-1_414]
[indo-pak_isu-5_761]
I am reading above file and want to remove lines from Need2Clean???.txt, trying via SED and GREP but no success.
myFile="NotRequired.txt"
while IFS= read -r HKline
do
sed -i '/$HKline/d' Need2CleanSED.txt
done < "$myFile"
myFile="NotRequired.txt"
while IFS= read -r HKline
do
grep -vE \"$HKline\" Need2CleanGRP.txt > Need2CleanGRP.txt
done < "$myFile"
Looks as if the Variable and characters [] making some problem.
What you're doing is extremely inefficient and error prone. Just do this:
grep -vF -f NotRequired.txt Need2CleanGRP.txt > tmp &&
mv tmp Need2CleanGRP.txt
Thanks to grep -F the above treats each line of NotRequired.txt as a string rather than a regexp so you don't have to worry about escaping RE metachars like [ and you don't need to wrap it in a shell loop - that one command will remove all undesirable lines in one execution of grep.
Never do command file > file btw as the shell might decide to execute the > file first and so empty file before command gets a chance to read it! Always do command file > tmp && mv tmp file instead.
Your assumption is correct. The [...] construct looks for any characters in that set, so you have to preface ("escape") them with \. The easiest way is to do that in your original file:
sed -i -e 's:\[:\\[:' -e 's:\]:\\]:' "${myFile}"
If you don't like that, you can probably put the sed command in where you're directing the file in:
done < replace.txt|sed -e 's:\[:\\[:' -e 's:\]:\\]:'
Finally, you can use sed on each HKline variable:
HKline=$( echo $HKline | sed -e 's:\[:\\[:' -e 's:\]:\\]:' )
try gnu sed:
sed -Ez 's/\n/\|/g;s!\[!\\[!g;s!\]!\\]!g; s!(.*).!/\1/d!' NotRequired.txt| sed -Ef - Need2CleanSED.txt
Two sed process are chained into one by shell pipe
NotRequired.txt is 'slurped' by sed -z all at once and substituted its \n and [ meta-char with | and \[ respectively of which the 2nd process uses it as regex script for the input file, ie. Need2CleanSED.txt. 1st process output;
/\[abc-xyz_pqr-pe2_123\]|\[lon-abc-tkt_1202\]|\[wat-7600-1_414\]|\[indo-pak_isu-5_761\]/d
add -u ie. unbuffered, option to evade from batch process, sort of direct i/o
I've writted a sed script to replace all ^^ with NULL. It seems though that sed is only catching a pair, but not including the second in that pair as it continues to search.
echo "^^^^" | sed 's/\^\^/\^NULL\^/g'
produces
^NULL^^NULL^
when it should produce
^NULL^NULL^NULL^
Try with a loop to apply your command again to modified pattern space:
echo "^^^^" | sed ':a;s/\^\^/\^NULL\^/;t a;'
To edit a file in place on OSX, try the -i flag and multiline command:
sed -i '' ':a
s/\^\^/\^NULL\^/
t a' file
With GNU sed:
sed -i ':a;s/\^\^/\^NULL\^/;t a;' file
or simply redirect the command to a temporary file before renaming it:
sed ':a;s/\^\^/\^NULL\^/;t a;' file > tmp && mv tmp file
I really like SLePort solution, but since it is not working for you, you can try with (tested on Linux, not Mac):
echo "^^^^" | sed 's/\^\^/\^NULL\^/g; s//\^NULL\^/g'
It is doing the same as the former solution, but explicitly, not looping with tags.
You can omit the pattern in the second command and sed will use the previous pattern.
I am using sed command in a shell script to edit & replace some file content of an xml file in a osx(unix) environment. Is there some way I can avoid sed creating the temporary files with -e ? I am doing the following in my script to edit a file with sed.
sed -i -e 's/abc/xyz/g' /PathTo/MyEditableFile.xml
Above sed command works great but creates an extra file as /PathTo/MyEditableFile.xml-e
How can I avoid creation of the the extra file with -e there ?
I tried some options like setting a temporary folder path to sed so that it creates the temporary file in /tmp/. Like so:
sed -i -e 's/abc/xyz/g' /PathTo/MyEditableFile.xml >/tmp
But doesnt seem to work
As you are editing the file in place (-i), OS X sed requires a mandatory backup filename.
You can use -i "" to get around this:
sed -i "" -e 's/abc/xyz/g' /PathTo/MyEditableFile.xml
I recently wrote a script that does a sed command, to replace all the occurrences of "string1" with "string2" in a file named "test.txt".
It looks like this:
sed -i 's/string1/string2/g' test.txt
The catch is, "string1" does not necessarily exist in test.txt.
I notice after executing a bunch of these sed commands, I get a number of empty files, left behind in the directory, with names that look like this:
"sed4l4DpD"
Does anyone know why this might be, and how I can correct it?
-i is the suffix given to the new/output file. Also, you need -e for the command.
Here's how you use it:
sed -i '2' -e 's/string1/string2/g' test.txt
This will create a file called test.txt2 that is the backup of test.txt
To replace the file (instead of creating a new copy - called an "in-place" substitution), change the -i value to '' (ie blank):
sed -i '' -e 's/string1/string2/g' test.txt
EDIT II
Here's actual command line output from a Mac (Snow Leopard) that show that my modified answer (removed space from between the -i and the suffix) is correct.
NOTE: On a linux server, there must be no space between it -i and the suffix.
> echo "this is a test" > test.txt
> cat test.txt
this is a test
> sed -i '2' -e 's/a/a good/' test.txt
> ls test*
test.txt test.txt2
> cat test.txt
this is a good test
> cat test.txt2
this is a test
> sed -i '' -e 's/a/a really/' test.txt
> ls test*
test.txt test.txt2
> cat test.txt
this is a really good test
I wasn't able to reproduce this with a quick test (using GNU sed 4.2.1) -- but strace did show sed creating a file called sedJd9Cuy and then renaming it to tmp (the file named on the command line).
It looks like something is going wrong after sed creates the temporary file and before it's able to rename it.
My best guess is that you've run out of room in the filesystem; you're able to create a new empty file, but unable to write to it.
What does df . say?
EDIT:
I still don't know what's causing the problem, but it shouldn't be too difficult to work around it.
Rather than
sed -i 's/string1/string2/g' test.txt
try something like this:
sed 's/string1/string2/g' test.txt > test.txt.$$ && mv -f test.txt.$$ test.txt
Something is going wrong with the way sed creates and then renames a text file to replace your original file. The above command uses sed as a simple input-output filter and creates and renames the temporary file separately.
So after much testing last night, it turns out that sed was creating these files when trying to operate on an empty string. The way i was getting the array of "$string1" arguments was through a grep command, which seems to be malformed. What I wanted from the grep was all lines containing something of the type "Text here '.'".
For example the string, "Text here 'ABC.DEF'" in a file, should have been caught by grep, then the ABC.DEF portion of the string, would be substituted by ABC_DEF. Unfortunately the grep I was using would catch lines of the type "Text here ''" (that is, nothing between the ''). When later on, the script attempted to perform a sed replacement using this empty string, the random file was created (probably because sed died).
Thanks for all your help in understanding how sed works.
Its better if you do it in this way:
cat large_file | sed 's/string1/string2/g' > file_filtred