Does Bash support non-greedy regular expressions? Even dash supports [^chars], but not posh. ... How to check if a string contains a substring in Bash. Regular Expression to Given a list of strings (words or other characters), only return the strings that do not match. grep , expr , sed and awk are some of them.Bash also have =~ operator which is named as RE-match operator.In this tutorial we will look =~ operator and use cases.More information about regex command cna be found in the following tutorials. [^chars] is merely a commonly-supported extension. 3. * All of the extglob quantifiers supported by bash were supported by ksh88. Since 3.0, Bash supports the =~ operator to the [[ keyword. The most significant difference between globs and Regular Expressions is that a valid Regular Expressions requires a qualifier as well as a quantifier. Bash regex matching not working in 4.1. 1. To do a case insensitive match in bash, you can use the nocasematch option: That applies to shell pattern matching â¦ Unix/Linux find command âpatternsâ FAQ: How do I find files or directories that donât match a specific pattern (files not matching a regex pattern, or filename pattern)?. Sed command that would ignore any commented match. Regular expressions (regex) are similar to Glob Patterns, but they can only be used for pattern matching, not for filename matching. Bash regex, match string beween two strings. 1. Bash does not process globs that are enclosed within "" or ''. With regular expressions you need to use the ^ or $ to anchor the pattern respectively at the start and end of the subject if you want to match the subject as a whole and not within it. * Counter-intuitively, only the [!chars] syntax for negating a character class is specified by POSIX for shell pattern matching. Difference to Regular Expressions. 3866. I'd like to be able to match based on whether it has one or more of those strings -- or possibly all. Simple Regex match not working. Regular expressions are great at matching. Regular expression to match a line that doesn't contain a word. Where in the documentation does it say that . Bash regex test not working. Related. Linux bash provides a lot of commands and features for Regular Expressions or regex. A qualifier identifies what to match and a quantifier tells how often to match the qualifier. R-egular E-xpression MATCH-ing (the first many times I read the word "rematch", I just could not help my thoughts drifting back to Hulk Hogan taking on André the Giant at WrestleMania IV- those were the days...) is performed using commands on the form: Regular Expression Matching (REMATCH) Match and extract parts of a string using regular expressions. 6. Stating a regex in terms of what you don't want to match is a bit harder. Regular expressions is not the same as shell pattern matchingâ¦ 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! This operator matches the string that comes before it against the regex pattern that follows it. And while I'm comparing glob patterns to regular expressions, there's an important point to be made that may not be immediately obvious: glob patterns are just another syntax for doing pattern matching in general in bash. I'm sure this is simple, I just can't get my brain around it. 1. It's easy to formulate a regex using what you want to match. 1. bash regex does not recognize all groups. And you can use them in a number of different places: After the == in a bash [[ expr ]] expression. Non greedy text matching and extrapolating in bash. 2377. means any character in pattern matching? How can I check if a directory exists in a Bash shell script? In man bash it says: Pattern Matching Any character that appears in a pattern, other than the special pattern characters described below, matches itself. 2. Regex OR ( Not working) 1. 4521. One easy way to exclude text from a match is negative lookbehind: w+b(?