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How to quote variable in grep regex Stack Overflow?
You can also use a backslash to quote a $ if you’re using double quotes. Also, you may need to put your variable in curly braces $ {var} in order to help separate it from the rest of the pattern. Thanks for contributing an answer to Stack Overflow!
When to use shell-grep on a variable?
If $_occur is either empty or unset when it is invoked then it will affect no shell variables at all and return 1 if “$2” occurs in “$1” fewer than “$3” times. Or, if called with only two args, it will return 1 only if “$2” is not in “$1”.
How to get grep to read on standard input?
Have grep read on its standard input. There you go, using a pipe or a here string or you could ask grep to print the match only: This will allow you to get rid of the rest of the line when there’s a match. Edit: Oops, read a little too fast, thanks Marco.
How to grep on a variable or grep a string from a variable?
Using the here string allows you to easily grep a string from a variable. Counting the Instances of a String in a Variable. You can use the wc utility to count the number of times a string is found in a variable. To do this, you must first tell grep to only show the matching characters with the -o (–only-matching) option. Then you can pipe it
Is there a problem with grep ” pattern$ “?
Following explains it. The problem with all double quotes is following: grep “pattern$” gives following error: Illegal variable name. And using all single quotes works, but if you want variable substitution, all single quotes will not work. For example: If I have string A_BOOK, including other strings in a file FILE.
How to find the end of a line in grep?
The $ anchor matches the end of a line. In addition to your question please note that .rar does not only match “.rar” but matches every single character (including .) before the rar. In this case probably not a problem but . must be escaped in regexes. You can also instruct grep to look for your string starting at a word boundary.