When to use sed to replace second occurrence of a word?

When to use sed to replace second occurrence of a word?

But from the output, you can see that ‘sed’ is not replacing 2nd occurrence of the world ‘line’. So, am I making any mistake here? s/../../2 is replacing the second occurrence of each line. The 2s is to make the change on the second line. Your command would only work if the string line appeared more than once on one or more lines.

Do you need to quote the sed command?

I believe \\< and \\> work with gnu sed, you just need to quote the sed command: The only difference here is that I’ve enclosed the command in single quotes. Even when it is not necessary to quote a sed command, I see very little disadvantage to doing so (and it helps avoid these kinds of problems).

How to replace sample name in regex-SED?

If “sample_name” occurs like this ifsample_name and you want to replace that as well then you should use the following: So that it replaces only the desired word. For example the above syntax will replace word “the” from a text file and not from words like thereby.

How to print last word from last word in SED?

If that is the case, you could simply say: to get the desired lines. This will look lines between 13 to 17 then search for Name and if match then it will print last word from Name = LastWord You don’t need any other tool for this, sed will easily handle it entire.

How to match whole words in SED on Mac?

\\b in regular expressions match word boundaries (i.e. the location between the first word character and non-word character): On Mac OS X, neither of these regex syntaxes work inside sed for matching whole words Hear me now and believe me later, this ugly syntax is what you need to use:

How to replace Minty with Minty in SED?

On Mac OS X, neither of these regex syntaxes work inside sed for matching whole words Hear me now and believe me later, this ugly syntax is what you need to use: So, for example, to replace mint with minty for whole words only: In one of my machine, delimiting the word with ” \\b ” (without the quotes) did not work.

How to match the first allow in a SED?

Here we match the first Allow then we ignore the substitution for the first Allow we come across and substitute the next line. sed ‘0,/Allow/! {N;/Allow/s/Allow/Deny/}’ We match Allow then keep a counter c. If this matches the 2 second occurrence then we substitute it.

How to replace the nth occurrence of a string using SED?

Then pass it to sed and tell it to replace the nth occurrence of your string. Finally, pass the output back through tr to recreate the newlines. It can also be done with sed, WITHOUT changing the newlines first, using the following command: Thanks for contributing an answer to Stack Overflow!

How to create a single string in SED?

First replace all the newlines with a unique character that does not occur anywhere else in your file (e.g. ^) using tr. You need to do this in order to create a single string for sed. Then pass it to sed and tell it to replace the nth occurrence of your string.

How to replace the last occurrence in a string?

`sed` command can be used to replace any part of a string or a line of the file in different ways by using regular expression patterns. This tutorial showed the ways to replace the last occurrence of the searching text in a string or a file by using multiple `sed` commands.

How to replace first k instances of Linux?

Say file foo.txt contains 100 instances occurrences of word ‘linux’ . I need to replace first 50 occurrences only. The first section belows describes using sed to change the first k-occurrences on a line. The second section extends this approach to change only the first k-occurrences in a file, regardless of what line they appear on.

How to change the first K of a word in a file?

The first section belows describes using sed to change the first k-occurrences on a line. The second section extends this approach to change only the first k-occurrences in a file, regardless of what line they appear on. With standard sed, there is a command to replace the k-th occurrance of a word on a line.

How is SED used to find and replace string in files?

Quite often when working with text files you’ll need to find and replace strings of text in one or more files. sed is a stream editor. It can perform basic text manipulation on files and input streams such as pipelines. With sed you can search, find and replace, insert, and delete words and lines.