How to replace multiple patterns at once with SED?

How to replace multiple patterns at once with SED?

Since there was a answer saying that sed is a stream editor and its replaces are greedily I think that I will need to use some script language for that. Replace ~ with a character that you know won’t be in the string. some text AB some more text “BC” and more text. some text BC some more text “CD” and more text.

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 use unique markers in SED?

An unique marker (in this case ) is prepended to the start of the line and used as a method to bump-along the search throughout the length of the line. Once the marker reaches the end of the line the process is finished and is printed out the lookup table and markers being discarded.

What does three newlines mean in SED syntax?

Three newlines means that a value is “locked-in”, like your original post way trying to do with ab and bc. After that point, further replacements will be undone, because they are protected by the newlines. A little complicated if I don’t say so myself… ! sed isn’t really meant for much more than the basics.

Why do you never get a newline in SED?

This is because since sed is 100% line-based, a newline is the one-and-only character you are guaranteed to never receive when a new line is fetched (forget about GNU multi-line extensions for this discussion).

How to replace multiple words in a string?

I’m trying to replace multiple words in a string with multiple other words. The string is “I have a cat, a dog, and a goat.” However, this does not produce “I have a dog, a goat, and a cat”, but instead it produces “I have a cat, a cat, and a cat”.

How to search for multiple patterns in a file?

Search Recursively for Multiple Patterns in a File. The grep command searches only in the current directory when you use the asterisk wildcard. To include all subdirectories when searching for multiple patterns, add the -R operator to grep: grep -R ‘warning|error’ /var/log/*.log.

How to grep for multiple strings, patterns or words?

How to Grep Multiple Patterns – Syntax The basic grep syntax when searching multiple patterns in a file includes using the grep command followed by strings and the name of the file or its path. The patterns need to be enclosed using single quotes and separated by the pipe symbol. Use the backslash before pipe | for regular expressions.

Is there a simple way to replace tabs?

This ought to be really simple, but for some reason it is not working: Instead of replacing tab characters, it’s replacing t characters. I’ve tried every variation on this I could think of, playing with quoting, etc. I’ve Googled and found everyone else using pretty similar expressions and they seem to work for them. The -E is an OS X thing.

What does the replacement pattern$ 1 mean?

For example, the replacement pattern $1 indicates that the matched substring is to be replaced by the first captured group. For more information about numbered capturing groups, see Grouping Constructs. All digits that follow $ are interpreted as belonging to the number group.

Do you overwrite unprocessed characters in a pattern?

Since pattern length is always more than equal to 1 and replacement is only 1 character long, we would never overwrite unprocessed characters i.e j >= i is invariant. The time complexity of above algorithm is O (n*m), where n is length of string and m is length of the pattern.

Which is the command for multi-line operations in SED?

sed has three commands to manage multi-line operations: N, D and P (compare them to normal n, d and p ). In this case, you can match the first line of your pattern, use N to append the second line to pattern space and then use s to do your substitution.

How to replace a line in a text file with SED?

I have also written a related article on setting and replacing values in a properties file using sed. In these examples, we will be dealing with a text file named “text.txt” that contains the following content: The simplest case is replacing an entire line by finding the line that starts with the match.

How to match patterns on the same line?

If a number is on the line, print it (to handle the case where no number are found. It can also be done the other way around, first dropping lines without numbers: where abcfile would have as an example -y / -f / +incdir+ patterns , when patterns are matched it will insert new line before it.

Why is my regex not working with SED?

In the simplest calling of sed, it has one line of text in the pattern space, ie. 1 line of n delimited text from the input. The single line in the pattern space has no n… That’s why your regex is not finding anything.

How does SED handle a multi line string?

Nested Reads By default, when sed reads a line in the pattern space, it discards the terminating newline ( ) character. Nevertheless, we can handle multi-line strings by doing nested reads for every newline. 2.1. Pattern Space as Sliding Window

Which is an example of a substitution in SED?

Example 1 – sed & Usage: Substitute /usr/bin/ to /usr/bin/local. In the above example ‘&’ in the replacement part will replace with /usr/bin which is matched pattern and add it with /local. Example 2 – sed & Usage: Match the whole line. & replaces whatever matches with the given REGEXP.

How to replace whole line with SED in shell?

It gets the full line containing six and replaces it with fault. More generally, you can use an expression sed ‘/match/s/.*/replacement/’ file. This will perform the sed ‘s/match/replacement/’ expression in those lines containing match. In your case this would be:

Which is the best character to use with SED?

If you are going to do this, however, and your usage might involve more than some trivial string (maybe you are filtering data, etc.), the best character to use with sed is a newline.

Are there lines after pattern matching excluding lines?

This shows the immediate next line to the pattern. Not showing ALL the lines. Last edited by Scrutinizer; 06-05-2014 at 06:09 AM.. Does your server support the -A flag on grep?

How to print lines between two patterns, inclusive or exclusive?

{/PAT2/!p;};}’ patternTester >> sedTesterOutput; done sed solutions seems to be twice as fast as the awk solution (Mac OS). This might work for you (GNU sed) on the proviso that PAT1 and PAT2 are on separate lines: Turn off implicit printing by using the -n option and act like grep.

How to parametrize the SED line in send?

One more thing the sed line should be able to be parametrized to set false -> true or true -> false, but only for SUT_INST_EXAMPLES & SUT_INST_PING. Solution (according to @RomanPerekhrest) and how to use it in send (expect script):