I tried a few different ways I came up with (e.g., [0-9]+ or ^[0-9][0-9]*$ ); none of them works. Thanks. bash case regex, Is there any way other than putting the two character cases [Ss] for each character because it is not about the initials, but all the characters can come in any case? I keep finding conflicting information regarding the ability to use regex in a bash case statement. Last edited by radoulov; 04-28-2014 at 04:10 PM .. ‘,’ symbol is used to convert the first character of the string to lowercase and ‘,,’ symbol is used to convert the whole string to the lowercase. It is the most popular editor amongst Linux Journal readers. I looked at previous posts but there are not like my case. I've been using the following regex below in a bash script on RHEL 5.5 using version GNU bash, version 3.2.25(1)-release I've tried using the script on RHEL 6.3 which uses GNU bash, version 4.1.2(1)-release I assume there's been alot of changes to bash since that's quite a jump in revisions.... (12 Replies) Is this possible and if so what is the proper syntax when using regex for the pattern to match? (patterns) (regex)? It enable you to match several values against one variable. Think of it terms of regular expressions: Glob Regular Expression Equivalent Description? 1)Basic Regular expressions. 3)Extended Regular expressions (Use option -E for grep and … How can I write a case statement using regex as condition (to match numbers)? The egrep command is the same as the grep -E combination, you just don’t have to use the -E option every time. Also, refer to our earlier article on Bash ~ expansaion and { } expansion. I know that BASH =~ regex can be system-specific, based on the libs available -- in this case, this is primarily CentOS 6.x (some OSX Mavericks with Macports, but not needed) Thanks! You can convert the case of the string more easily by using the new feature of Bash 4. ‘^’ symbol is used to convert the first character of any string to uppercase and ‘^^’ symbol is used to convert the whole string to the uppercase. After deleting the lines matches with the pattern Vim: $ ./fileop.sh -d Vim text It is the most popular editor amongst Linux Journal readers. This post for example shows how to make regex case insensitive when using list of characters []. Bash Case Example 3. The bash man page refers to glob patterns simply as "Pattern Matching". ← Exit command • Home • Dealing with case sensitive pattern →. One can test that a bash variable starts with a string or character in bash efficiently using any one of the following methods. Bash case regex output. (Recommended Read: Bash Scripting: Learn to use REGEX (Part 2- Intermediate)) Also Read: Important BASH tips tricks for Beginners For this tutorial, we are going to learn some of regex basics concepts & how we can use them in Bash using ‘grep’, but if you wish to use them on other languages like python or C, you can just use the regex part. Regular expressions (Regexp) is one of the advanced concept we require to write efficient shell scripts and for effective system administration. In the patterns to a case command. Pattern matching in a bash case statement using regex. To use the extended regular expressions with grep, you have to use the -E (extended) option. Solution # 2: Use regex with case patterns. It is easier to read and write. The case statement is good alternative to multilevel if-then-else-fi statement. 2)Interval Regular expressions (Use option -E for grep and -r for sed). Because this gets tiresome very quickly, the egrep command was created. 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