sed 's/$/<br>/' mytext.txt
worked but output it all on the command line. I want it to just do the replacement WITHIN the specified file itself. Should I be using another tool?
If you have gnu sed, you can use the -i option, which will do the replacement in place.
sed -i 's/$/<br>/' mytext.txt
Otherwise you will have to redirect to another file and rename it over the old one.
sed 's/$/<br>/' mytext.txt > mytext.txt.new && mv mytext.txt.new mytext.txt
Just for completeness. On Mac OS X (which uses FreeBSD sed) you have to use an additional null-string "" for in-place file editing without backup:
sed -i "" 's/$/<br>/' mytext.txt
As an alternative to using sed for no-backup in-place file editing, you may use ed(1), which, however, reads the entire file into memory before operating on it.
printf '%s\n' H 'g/$/s//<br>/g' ',p' | ed -s test.file # print to stdout
printf '%s\n' H 'g/$/s//<br>/g' wq | ed -s test.file # in-place file edit
For more information on ed(1) see:
"Editing files with the ed text editor from scripts",
http://wiki.bash-hackers.org/doku.php?id=howto:edit-ed
If you have an up-to-date sed, just use sed -i or sed --in-place, which will modify the actual file itself.
If you want a backup, you need to supply a suffix for it. So sed -i.bak or sed --in-place=.bak will create a backup file with the .bak suffix.
Use this! Seriously! You'll appreciate it a lot the first time you damage your file due to a mistyped sed command or wrong assumption about the data in the file.
Use the redirection symbol i.e.
sed 's/$/<br>/' mytext.txt > mytext2.txt && mv mytext2.txt mytext.txt
Related
How would I use sed to delete all lines in a text file that contain a specific string?
To remove the line and print the output to standard out:
sed '/pattern to match/d' ./infile
To directly modify the file – does not work with BSD sed:
sed -i '/pattern to match/d' ./infile
Same, but for BSD sed (Mac OS X and FreeBSD) – does not work with GNU sed:
sed -i '' '/pattern to match/d' ./infile
To directly modify the file (and create a backup) – works with BSD and GNU sed:
sed -i.bak '/pattern to match/d' ./infile
There are many other ways to delete lines with specific string besides sed:
AWK
awk '!/pattern/' file > temp && mv temp file
Ruby (1.9+)
ruby -i.bak -ne 'print if not /test/' file
Perl
perl -ni.bak -e "print unless /pattern/" file
Shell (bash 3.2 and later)
while read -r line
do
[[ ! $line =~ pattern ]] && echo "$line"
done <file > o
mv o file
GNU grep
grep -v "pattern" file > temp && mv temp file
And of course sed (printing the inverse is faster than actual deletion):
sed -n '/pattern/!p' file
You can use sed to replace lines in place in a file. However, it seems to be much slower than using grep for the inverse into a second file and then moving the second file over the original.
e.g.
sed -i '/pattern/d' filename
or
grep -v "pattern" filename > filename2; mv filename2 filename
The first command takes 3 times longer on my machine anyway.
The easy way to do it, with GNU sed:
sed --in-place '/some string here/d' yourfile
You may consider using ex (which is a standard Unix command-based editor):
ex +g/match/d -cwq file
where:
+ executes given Ex command (man ex), same as -c which executes wq (write and quit)
g/match/d - Ex command to delete lines with given match, see: Power of g
The above example is a POSIX-compliant method for in-place editing a file as per this post at Unix.SE and POSIX specifications for ex.
The difference with sed is that:
sed is a Stream EDitor, not a file editor.BashFAQ
Unless you enjoy unportable code, I/O overhead and some other bad side effects. So basically some parameters (such as in-place/-i) are non-standard FreeBSD extensions and may not be available on other operating systems.
I was struggling with this on Mac. Plus, I needed to do it using variable replacement.
So I used:
sed -i '' "/$pattern/d" $file
where $file is the file where deletion is needed and $pattern is the pattern to be matched for deletion.
I picked the '' from this comment.
The thing to note here is use of double quotes in "/$pattern/d". Variable won't work when we use single quotes.
You can also use this:
grep -v 'pattern' filename
Here -v will print only other than your pattern (that means invert match).
To get a inplace like result with grep you can do this:
echo "$(grep -v "pattern" filename)" >filename
I have made a small benchmark with a file which contains approximately 345 000 lines. The way with grep seems to be around 15 times faster than the sed method in this case.
I have tried both with and without the setting LC_ALL=C, it does not seem change the timings significantly. The search string (CDGA_00004.pdbqt.gz.tar) is somewhere in the middle of the file.
Here are the commands and the timings:
time sed -i "/CDGA_00004.pdbqt.gz.tar/d" /tmp/input.txt
real 0m0.711s
user 0m0.179s
sys 0m0.530s
time perl -ni -e 'print unless /CDGA_00004.pdbqt.gz.tar/' /tmp/input.txt
real 0m0.105s
user 0m0.088s
sys 0m0.016s
time (grep -v CDGA_00004.pdbqt.gz.tar /tmp/input.txt > /tmp/input.tmp; mv /tmp/input.tmp /tmp/input.txt )
real 0m0.046s
user 0m0.014s
sys 0m0.019s
Delete lines from all files that match the match
grep -rl 'text_to_search' . | xargs sed -i '/text_to_search/d'
SED:
'/James\|John/d'
-n '/James\|John/!p'
AWK:
'!/James|John/'
/James|John/ {next;} {print}
GREP:
-v 'James\|John'
perl -i -nle'/regexp/||print' file1 file2 file3
perl -i.bk -nle'/regexp/||print' file1 file2 file3
The first command edits the file(s) inplace (-i).
The second command does the same thing but keeps a copy or backup of the original file(s) by adding .bk to the file names (.bk can be changed to anything).
You can also delete a range of lines in a file.
For example to delete stored procedures in a SQL file.
sed '/CREATE PROCEDURE.*/,/END ;/d' sqllines.sql
This will remove all lines between CREATE PROCEDURE and END ;.
I have cleaned up many sql files withe this sed command.
echo -e "/thing_to_delete\ndd\033:x\n" | vim file_to_edit.txt
Just in case someone wants to do it for exact matches of strings, you can use the -w flag in grep - w for whole. That is, for example if you want to delete the lines that have number 11, but keep the lines with number 111:
-bash-4.1$ head file
1
11
111
-bash-4.1$ grep -v "11" file
1
-bash-4.1$ grep -w -v "11" file
1
111
It also works with the -f flag if you want to exclude several exact patterns at once. If "blacklist" is a file with several patterns on each line that you want to delete from "file":
grep -w -v -f blacklist file
to show the treated text in console
cat filename | sed '/text to remove/d'
to save treated text into a file
cat filename | sed '/text to remove/d' > newfile
to append treated text info an existing file
cat filename | sed '/text to remove/d' >> newfile
to treat already treated text, in this case remove more lines of what has been removed
cat filename | sed '/text to remove/d' | sed '/remove this too/d' | more
the | more will show text in chunks of one page at a time.
Curiously enough, the accepted answer does not actually answer the question directly. The question asks about using sed to replace a string, but the answer seems to presuppose knowledge of how to convert an arbitrary string into a regex.
Many programming language libraries have a function to perform such a transformation, e.g.
python: re.escape(STRING)
ruby: Regexp.escape(STRING)
java: Pattern.quote(STRING)
But how to do it on the command line?
Since this is a sed-oriented question, one approach would be to use sed itself:
sed 's/\([\[/({.*+^$?]\)/\\\1/g'
So given an arbitrary string $STRING we could write something like:
re=$(sed 's/\([\[({.*+^$?]\)/\\\1/g' <<< "$STRING")
sed "/$re/d" FILE
or as a one-liner:
sed "/$(sed 's/\([\[/({.*+^$?]\)/\\\1/g' <<< "$STRING")/d"
with variations as described elsewhere on this page.
cat filename | grep -v "pattern" > filename.1
mv filename.1 filename
You can use good old ed to edit a file in a similar fashion to the answer that uses ex. The big difference in this case is that ed takes its commands via standard input, not as command line arguments like ex can. When using it in a script, the usual way to accomodate this is to use printf to pipe commands to it:
printf "%s\n" "g/pattern/d" w | ed -s filename
or with a heredoc:
ed -s filename <<EOF
g/pattern/d
w
EOF
This solution is for doing the same operation on multiple file.
for file in *.txt; do grep -v "Matching Text" $file > temp_file.txt; mv temp_file.txt $file; done
I found most of the answers not useful for me, If you use vim I found this very easy and straightforward:
:g/<pattern>/d
Source
I've writted a sed script to replace all ^^ with NULL. It seems though that sed is only catching a pair, but not including the second in that pair as it continues to search.
echo "^^^^" | sed 's/\^\^/\^NULL\^/g'
produces
^NULL^^NULL^
when it should produce
^NULL^NULL^NULL^
Try with a loop to apply your command again to modified pattern space:
echo "^^^^" | sed ':a;s/\^\^/\^NULL\^/;t a;'
To edit a file in place on OSX, try the -i flag and multiline command:
sed -i '' ':a
s/\^\^/\^NULL\^/
t a' file
With GNU sed:
sed -i ':a;s/\^\^/\^NULL\^/;t a;' file
or simply redirect the command to a temporary file before renaming it:
sed ':a;s/\^\^/\^NULL\^/;t a;' file > tmp && mv tmp file
I really like SLePort solution, but since it is not working for you, you can try with (tested on Linux, not Mac):
echo "^^^^" | sed 's/\^\^/\^NULL\^/g; s//\^NULL\^/g'
It is doing the same as the former solution, but explicitly, not looping with tags.
You can omit the pattern in the second command and sed will use the previous pattern.
how to add the current date in a each record as first column.
Input file:
12345|Test1
67890|Test2
expected Output file:
2014-04-26|12345|Test1
2014-04-26|67890|Test2
Thanks,
sed -e "s,^,$(date +'%Y-%M-%d')|," file
If you use Linux (more specifically, GNU sed) then you may use in-place editing with -i flag:
sed -i -e "s,^,$(date +'%Y-%M-%d')|," file
Otherwise you have to store results into a temporary file and then rename.
You could use awk
awk -vOFS='|' -vcdate=$(date '+%Y-%m-%d') ' {print cdate, $0}' file
You can use sed for example:
sed -i "/^$/ !s/^/`date +"%Y-%m-%d"`|/" data_file
If you want to edit the file, why not use ed, the standard editor? the common and nice versions of ed will support the following:
printf '%s\n' "$(date '+%%s/^/%Y-%m-%d|/')" wq | ed -s file
(this will edit the file in place, so make sure you have appropriate backups if you want to revert the changes).
On OSX I need to remove line-ending CR (\r) characters (represented as ^M in the output from cat -v) from my CSV file:
$ cat -v myitems.csv
output:
strPicture,strEmail^M
image1xl.jpg,me#example.com^M
I have tried lots of options with sed and perl but nothing works.
Any ideas?
Solutions with stock utilities:
Note: Except where noted (the sed -i incompatibility), the following solutions work on both OSX (macOS) and Linux.
Use sed as follows, which replaces \r\n with \n:
sed $'s/\r$//' myitems.csv
To update the input file in place, use
sed -i '' $'s/\r$//' myitems.csv
-i '' specifies updating in place, with '' indicating that no backup should be made of the input file; if you specify a extension, e.g., -i'.bak', the original input file will be saved with that extension as a backup.
Caveats:
* With GNU sed (Linux), to not create a backup file, you'd have to use just -i, without the separate '' argument, which is an unfortunate syntactic incompatibility between GNU Sed and the BSD Sed used on OSX (macOS) - see this answer of mine for the full story.
* -i creates a new file with a temporary name and then replaces the original file; the most notably consequence is that if the original file was a symlink, it is replaced with a regular file; for a detailed discussion, see the lower half of this answer.
Note: The above uses an ANSI C-quoted string ($'...') to create the \r character in the sed command, because BSD sed (the one used on OS X), doesn't natively recognize such escape sequences (note that the GNU sed used on Linux distros would).
ANSI C-quoted strings are supported in Bash, Ksh, and Zsh.
If you don't want to rely on such strings, use:
sed 's/'"$(printf '\r')"'$//'
Here, the \r is created via printf and spliced into the sed command with a command substitution ($(...)).
Using perl:
perl -pe 's/\r\n/\n/' myitems.csv | cat -v
To update the input file in place, use
perl -i -ple 's/\r\n/\n/' myitems.csv # -i'.bak' creates backup with suffix '.bak' first
The same caveat as above for sed with regard to in-place updating applies.
Using awk:
awk '{ sub("\r$", ""); print }' myitems.csv # shorter: awk 'sub("\r$", "")+1'
BSD awk offers no in-place updating option, so you'll have to capture the output in a different file; to use a temporary file and have it replace the original afterward, use the following idiom:
awk '{ sub("\r$", ""); print }' myitems.csv > tmpfile && mv tmpfile myitems.csv
GNU awk v4.1 or higher offers -i inplace for in-place updating, to which the same caveat as above for sed applies.
Edge case for all variants above: If the very last char. in the input file happens to be a lone \r without a following \n, it will also be replaced with a \n.
For the sake of completeness: here are additional, possibly suboptimal solutions:
None of them offer in-place updating, but you can employ the > tmpfile && mv tmpfile myitems.csv idiom introduced above
Using tr: a very simple solution that simply removes all \r instances; thus, it can only be used if \r instance only occur as part of \r\n sequences; typically, however, that is the case:
tr -d '\r' < myitems.csv
Using pure bash code: note that this will be slow; like the tr solution, this can only be used if \r instance only occur as part of \r\n sequences.
while IFS=$'\r' read -r line; do
printf '%s\n' "$line"
done < myitems.csv
$IFS is the internal field separator, and setting it to \r causes read to read everything before \r, if present, into variable $line (if there's no \r, the line is read as is). -r prevents read from interpreting \ instances in the input.
Edge case: If the input doesn't end with \n, the last line will not print - you could fix that by using read -r line || [[ -n $line ]].
try this, it will fix your issue.
dos2unix myitems.csv myitems.csv
Try the unix2dos command.
Example: unix2dos infile outfile
http://en.wikipedia.org/wiki/Unix2dos
The wikipedia page has some examples using perl and sed too.
perl -i -p -e 's/\n/\r\n/' file
sed -i -e 's/$/\r/' file
I'd like edit a file with sed on OS X. I'm using the following command:
sed 's/oldword/newword/' file.txt
The output is sent to the terminal. file.txt is not modified. The changes are saved to file2.txt with this command:
sed 's/oldword/newword/' file1.txt > file2.txt
However I don't want another file. I just want to edit file1.txt. How can I do this?
I've tried the -i flag. This results in the following error:
sed: 1: "file1.txt": invalid command code f
You can use the -i flag correctly by providing it with a suffix to add to the backed-up file. Extending your example:
sed -i.bu 's/oldword/newword/' file1.txt
Will give you two files: one with the name file1.txt that contains the substitution, and one with the name file1.txt.bu that has the original content.
Mildly dangerous
If you want to destructively overwrite the original file, use something like:
sed -i '' 's/oldword/newword/' file1.txt
^ note the space
Because of the way the line gets parsed, a space is required between the option flag and its argument because the argument is zero-length.
Other than possibly trashing your original, I’m not aware of any further dangers of tricking sed this way. It should be noted, however, that if this invocation of sed is part of a script, The Unix Way™ would (IMHO) be to use sed non-destructively, test that it exited cleanly, and only then remove the extraneous file.
I've similar problem with MacOS
sed -i '' 's/oldword/newword/' file1.txt
doesn't works, but
sed -i"any_symbol" 's/oldword/newword/' file1.txt
works well.
The -i flag probably doesn't work for you, because you followed an example for GNU sed while macOS uses BSD sed and they have a slightly different syntax.
All the other answers tell you how to correct the syntax to work with BSD sed. The alternative is to install GNU sed on your macOS with:
brew install gsed
and then use it instead of the sed version shipped with macOS (note the g prefix), e.g:
gsed -i 's/oldword/newword/' file1.txt
If you want GNU sed commands to be always portable to your macOS, you could prepend "gnubin" directory to your path, by adding something like this to your .bashrc/.zshrc file (run brew info gsed to see what exactly you need to do):
export PATH="/usr/local/opt/gnu-sed/libexec/gnubin:$PATH"
and from then on the GNU sed becomes your default sed and you can simply run:
sed -i 's/oldword/newword/' file1.txt
sed -i -- "s/https/http/g" file.txt
You can use -i'' (--in-place) for sed as already suggested. See: The -i in-place argument, however note that -i option is non-standard FreeBSD extensions and may not be available on other operating systems. Secondly sed is a Stream EDitor, not a file editor.
Alternative way is to use built-in substitution in Vim Ex mode, like:
$ ex +%s/foo/bar/g -scwq file.txt
and for multiple-files:
$ ex +'bufdo!%s/foo/bar/g' -scxa *.*
To edit all files recursively you can use **/*.* if shell supports that (enable by shopt -s globstar).
Another way is to use gawk and its new "inplace" extension such as:
$ gawk -i inplace '{ gsub(/foo/, "bar") }; { print }' file1
This creates backup files. E.g. sed -i -e 's/hello/hello world/' testfile for me, creates a backup file, testfile-e, in the same dir.
You can use:
sed -i -e 's/<string-to-find>/<string-to-replace>/' <your-file-path>
Example:
sed -i -e 's/Hello/Bye/' file.txt
This works flawless in Mac.
If you need to substitute more than one different words:
sed -i '' -e 's/_tools/tools/' -e 's/_static/static/' test.txt