How to delete all blank lines in the file with the help of python?
For example, we have some file like that:
text-processing
How to get only the unique results without having to sort data?
$ cat data.txt aaaaaa aaaaaa cccccc aaaaaa aaaaaa bbbbbb $ cat data.txt | uniq aaaaaa cccccc aaaaaa bbbbbb $ cat data.txt | sort | uniq aaaaaa bbbbbb cccccc $ The result that I need is to display all the lines from the original file removing all the duplicates (not just the consecutive ones), while maintaining … Read more
Command to display first few and last few lines of a file
I have a file with many rows, and each row has a timestamp at the starting, like
How can I double the newlines in an output stream
When I have an output stream: a b c d e How can I double the newlines: a b c d e Answers: Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found … Read more
Best way to follow a log and execute a command when some text appears in the log
I have a server log that outputs a specific line of text into its log file when the server is up. I want to execute a command once the server is up, and hence do something like the following:
Grabbing the first [x] characters for a string from a pipe
If I have really long output from a command (single line) but I know I only want the first [x] (let’s say 8) characters of the output, what’s the easiest way to get that? There aren’t any delimiters.
Parse XML to get node value in bash script?
I would like to know how I can get the value of a node with the following paths:
Filter file by line number
Given a file L with one non-negative integer per line and text file F, what would be a fast way to keep only those lines in F, whose line number appears in file L?
Is there a tool that combines zcat and cat transparently?
When handling log files, some end up as gzipped files thanks to logrotate and others not. So when you try something like this:
Concatenate multiple files with same header
I have multiple files with the same header and different vectors below that. I need to concatenate all of them but I want only the header of first file to be concatenated and I don’t want other headers to be concatenated since they are all same.