How to globally replace strings in lines NOT starting with a certain pattern
You just need to negate the match using !: sed -i ‘/^##Input/! s/foo/bar/g’ myfile
sed
Using different delimiters in sed commands and range addresses
You can use an alternative regex delimiter as a search pattern by backslashing it: sed ‘\,some/path,d’ And just use it as is for the s command: sed ‘s,some/path,other/path,’ You probably want to protect other metacharacters, though; this is a good place to use Perl and quotemeta, or equivalents in other scripting languages. From man sed: … Read more
sed, replace first line
You can use sed with something like sed ‘1 s/^.*$/<?php/’ The 1 part only replaces the first line. Then, thanks to the s command, it replaces the whole line by <?php. To modify your files in-place, use the -i option of GNU sed.
sed command in dry run
Remove the -i and pipe it to less to paginate though the results. Alternatively, you can redirect the whole thing to one large file by removing the -i and appending > dryrun.out I should note that this script of yours will fail miserably with files that contain spaces in their name or other nefarious characters … Read more
How do I run the sed command with input and output as the same file?
sed -i (or the extended version, –in-place) will automate the process normally done with less advanced implementations, that of sending output to temporary file, then renaming that back to the original. The -i is for in-place editing, and you can also provide a backup suffix for keeping a copy of the original: sed -i.bak fileToChange … Read more
Combining two sed commands
sed is a scripting language. You separate commands with semicolon or newline. Many sed dialects also allow you to pass each command as a separate -e option argument. sed -i ‘s/File//g;s/MINvac\.pdb//g’ /home/kanika/standard_minimizer_prosee/r I also added a backslash to properly quote the literal dot before pdb, but in this limited context that is probably unimportant. For … Read more
Replace all double quotes with single quotes
You need to pass the g flag to sed: sed “s/\”https://stackoverflow.com/”/g”
How to use awk to print lines where a field matches a specific string?
In awk: awk ‘$2 == “LINUX” { print $0 }’ test.txt See awk by Example for a good intro to awk. In sed: sed -n -e ‘/^[0-9][0-9]* LINUX/p’ test.txt See sed by Example for a good intro to sed.
Remove all lines before a match with sed
try this (GNU sed only): sed ‘0,/^bin$/d’ ..output is: $sed ‘0,/^bin$/d’ file boot … sys tmp usr var vmlinuz
Remove non-ASCII characters from CSV
A perl oneliner would do: perl -i.bak -pe ‘s/[^[:ascii:]]//g’ <your file> -i says that the file is going to be edited inplace, and the backup is going to be saved with extension .bak.