Delete all lines beginning with a # from a file
All of the lines with comments in a file begin with #. How can I delete all of the lines (and only those … Read more
sed
Command to get nth line of STDOUT
Is there any bash command that will let you get the nth line of STDOUT? That is to say, something that would take … Read more
Change multiple files
The following command is correctly changing the contents of 2 files. sed -i ‘s/abc/xyz/g’ xaa1 xab1 But what I need to do is … Read more
How to show only next line after the matched one?
grep -A1 ‘blah’ logfile Thanks to this command for every line that has ‘blah’ in it, I get the output of the line … Read more
Retrieve last 100 lines logs
I need to retrieve last 100 lines of logs from the log file. I tried the sed command sed -n -e ‘100,$p’ logfilename … Read more
What are the differences between Perl, Python, AWK and sed? [closed]
As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, … Read more
How to insert a text at the beginning of a file?
So far I’ve been able to find out how to add a line at the beginning of a file but that’s not exactly … Read more
How to use sed to replace only the first occurrence in a file?
I would like to update a large number of C++ source files with an extra include directive before any existing #includes. For this … Read more
Environment variable substitution in sed
If I run these commands from a script: #my.sh PWD=bla sed ‘s/xxx/’$PWD”https://stackoverflow.com/” … $ ./my.sh xxx bla it is fine. But, if I … Read more
Error when using ‘sed’ with ‘find’ command on OS X: “invalid command code .”
Being forced to use CVS for a current client and the address changed for the remote repo. The only way I can find … Read more