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Why is the E flag not working in GNU sed?
GNU sed does not directly support the mode you want, although you can fake it with a more complex script if desired. Alternatively, Perl’s /e modifier to its s command does have the behaviour you’re looking for, but with Perl expressions instead. You are getting multiple replacement, but you don’t get multiple executions.
What is the purpose of-E in sed command?
In both cases s/foo/bar/ is the script that is executed by sed. The second option is more explicit, but that is probably not the reason that you often see -e used. The reason for that is that -e makes it possible to use more than one script with the same invocation of sed.
Why are the E and G flags not working together?
It has (roughly speaking) the same effect as: GNU sed does not directly support the mode you want, although you can fake it with a more complex script if desired. Alternatively, Perl’s /e modifier to its s command does have the behaviour you’re looking for, but with Perl expressions instead.
What does the E command do in Linux?
The documentation of /e is, for the record: This command allows one to pipe input from a shell command into pattern space. If a substitution was made, the command that is found in pattern space is executed and pattern space is replaced with its output.
What should I do if my SED is not working?
Finally, as a general rule you never use sed -i without first testing without the -i to be sure it works or, if you do, at least use -i.bak ( -i with any text will do this) to create a backup. And as an alternative to the sed I suggest using grep to extract data from a file:
What do you need to know about SED in Linux?
Description sed is a stream editor. If you do not specify INPUTFILE, or if INPUTFILE is “-“, sed filters the contents of the standard input. A sed program consists of one or more sed commands, passed in by one or more of the -e, -f, –expression, and –file options, or the first non-option argument if none of these options are used.
Why is the escape symbol not working in SED?
You are also escaping all sorts of things that don’t need to be escaped (neither the \\= nor the \\> are doing anything useful) while not escaping things that do need to be escaped ( + just means the symbol + in BRE, you need \\+ for “one or more”.