CODEWITHSUNDEEP
regexsed
vehomzzz
vehomzzz

Reputation: 44588

what does this sed commands does? please explain its bits and pieces

Please explain this sed command?

sed -n "s/[^>]*>/ /gp"

What is gp?

Upvotes: 2

Views: 2019

Answers (3)

tsalaroth
tsalaroth

Reputation: 112

I was typing up a long explanation, but Brian beat me to it. To clarify a tiny bit, the "p" prints the modified / matching line. The "-n" in your command line tells sed to "not print the file". Combined with the "p", it works kinda like grep, but within the scope of the script (ie, anything it changes/matches).

Upvotes: 1

Brian Clapper
Brian Clapper

Reputation: 26210

It looks for non-greater-than characters preceding a greater-than symbol, and changes all of them to a single space. Thus, it will convert this input (where I've used _ to indicate a space):

foo>_bar> b
x>>_a

to

___b
___a

As Mark notes, "g" means global, and "p" means "print the line".

Upvotes: 5

Mark Byers
Mark Byers

Reputation: 838326

  • g means global: i.e. replace all occurences, not just the first.
  • p means to print the modified line. Otherwise due to the -n switch it would not be printed.

The command finds all lines containing at least one > and prints some spaces followed by the text after the final >. The number of spaces printed is the number of > in the line.

For example if this line is in the input file:

123>456>789

Then this is printed:

  789

Upvotes: 3

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