tr – First Use

tr – Translate of Delete. This is the first time i am using this command and it was pretty nice. Used the gui repalce functionality on text editors so far and, sed recently. But this seems pretty nice.

tr 'abc' 'xyz' will replace the occurence of abc with xyz. Takes input from the standard input. Meaning if you run this command and type something in and press enter. You will see the results down below. Common use is to cat and pipeline the content though.

Sed – Quick Reference

Another personal reference

Two basic forms of use.
sed [-n] [-e] 'command(s)' files
sed [-n] -f scriptfile files

First one uses inline commands. The second one uses a script file. A command like delete or print can be executed based on an address/line range or a pattern. Lets look at the commands themselves in no particular order just to recollect things. All concepts are mixed and mashed.

  1. p stands for print and it prints the lines that are specified. ‘1p’ will print the first line.
  2. '1,5 p' will print the lines from one to five.
  3. '2, +3 p' will print line 2 and the next 3 lines as well.
  4. '2, ~4 p' will print line 2 and every fourth line from that. Meaning, 2, 6, 10, 14, 18, 22…
  5. Address and Pattern matching can be used together.'/hello/, 5 p' looks for the line that has ‘hello’ and then prints five lines that follow it.
  6. '/hello/, $ p' prints from the line that has the first occurence of hello till the end
  7. '/pattern1/ /pattern2/ p' prints all the lines that contains pattern 1 upto the line that contains pattern 2.
  8. d is for deleting a line. Similar to p, for printing.
  9. w can be used to write to a file after filtering some lines. Or with no filters at all, which would make it work like a cp command.
  10. 'w newfile' will make a copy of the target file into the new file
  11. '2,5 w newfile' will just write the lines 2 to 5 of the target file to the new file. Pattern matching can also be used instead of Address matching.
  12. a can be used to append a line to a file.
  13. '4 a text to be appended' appends the text to be appended to the file after line 4.
  14. c can be used for replacing or changing patterns or lines.
  15. '4 c text line to be replaced' will replace the fourth line with the text line to be replaced. Multiple lines can be replaced with single lines as well.
  16. i stands for insert.
  17. y for translate.
  18. Syntax for y [address1[,address2]]y/list-1/list-2/.
  19. [address1[,address2]]l shows hidden characters
  20. [address]q [value] for quit
  21. [address]r file read and insert contents of file into address of the target file specified
  22. [address1[,address2]]e [command] execute bash command on the address
  23. [address1[,address2]]s/pattern/replacement/[flags] substitute command
  24. 's/Paulo Coelho/PAULO COELHO/w junk.txt' replace and write to new file

More to be added to this post.