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How to replace first two occurrences in SED?
You’d need to capture the first two strings of digits, plus the separators to replace them, and not match the rest of the line: Substitution expressions in sed support a numeric flag. Here’s how GNU sed can do it: So what’s going on here? This expression has two parts, separated by ;. Here they are:
What is the interaction defined in GNU sed?
For GNU sed, the interaction is defined to be: ignore matches before the numberth, and then match and replace all matches from the numberth on. [ source] Thanks for contributing an answer to Unix & Linux Stack Exchange!
How to replace a string with a SED?
Almost any character should work, but be careful with the characters that need escaping in your environment, sed, etc. depending on how you intend to use the results. If replacing the string by Variable, the solution doesn’t work. The sed command need to be in double quotes instead on single quote.
How do you replace colons in GNU sed?
One way would be to replace colons one at a time using a loop, breaking out of the loop when the result contains two hyphens: Alternatively, if you have GNU sed, you could replace all the colons with hyphens, then replace from the third hyphen onward with colons again:
Which is the smallest possible range in SED?
So since range is inclusive, smallest possible range is “2 lines” and smallest starting range is both lines 1 and 2 (i.e. if there’s an occurrence on line 1, occurrences on line 2 will also be changed, not desired in this case).
How to compare two dates in format YYYY-MM-DD-SS?
I am trying to compare 2 dates in the format YYYY:MM:DD HH:MM:SS by using the date (bash) command. My problem is that the date command only uses the date format (as far as I know) YYYY-MM-DD HH:MM:SS.
How can I use sed to replace a multi line string?
The hold space however is preserved. Finally, on the very last line, g restores the accumulation of every line from the hold space so that sed is able to run its regex on the whole input (rather than in a line-at-a-time fashion), and hence is able to match on s.
Which is the first line in a SED?
Background: In traditional sed the range specifier is also “begin here” and “end here” (inclusive). However the lowest “begin” is the first line (line 1), and if the “end here” is a regex, then it is only attempted to match against on the next line after “begin”, so the earliest possible end is line 2.