What does the p mean in the sed command?
The p means “print matched lines.” By default, sed prints all lines. We’d see all the text in the file with the matching lines printed twice. To prevent this, we’ll use the -n (quiet) option to suppress the unmatched text.
What does the E flag mean in SED?
The -e flag means sed should execute the following string as a command. The s is the search-and-replace command. Normally, sed replaces only the first occurrence of the search string in each line, but the final g tells it to replace it g lobally, that is, to replace every occurrence.
Why does SED stop after the first match?
In the first line, only the second occurrence of “day” is changed. This is because sed stops after the first match per line. We have to add a “g” at the end of the expression, as shown below, to perform a global search so all matches in each line are processed: This matches three out of the four in the first line.
Are there comments at the end of a line in SED?
When I first wrote this (in 1994), most versions of sed did not allow you to place comments inside the script. Lines starting with the ‘#’ characters are comments. Newer versions of sed may support comments at the end of the line as well.
What does the comma mean in the sed command?
A single number selects that one line. Note the comma between 1 and 4. The p means “print matched lines.” By default, sed prints all lines. We’d see all the text in the file with the matching lines printed twice.
How does the command line work in GNU sed?
Add the commands contained in the file script-file to the set of commands to be run while processing the input. This option specifies that files are to be edited in-place. GNU sed does this by creating a temporary file and sending output to this file rather than to the standard output.
How to change SED between specific lines only?
How can i change it that, it will make the modification between only specific line numbers. (e.g. between second and third lines). Since OSX (BSD sed) has some syntax differences to linux (GNU) sed, thought I’d add the following from some hard-won notes of mine: