Unix grep multiple strings in a file

Quick Links. Search Forums. Show Threads. Show Posts. Shell Programming and Scripting. Grep multiple strings in a file. Registered User. Join Date: Jun Originally Posted by Yoda. Code :. Originally Posted by Don Cragun. Don Cragun. Join Date: Jul You wouldn't answer what operating system you're using, but it is likely either a Solaris operating system or a Linux operating system; both of which either have ksh or bash available for your use. And, the commands Akshay gave you should work with both ksh and bash.

How to pass strings from a list of strings from another file and create multiple files? Hello Everyone , Iam a newbie to shell programming and iam reaching out if anyone can help in this :- I have two files 1 Insert. Grep and replace multiple strings in a file with multiple filenames in a file. The difference between grep and extended grep is that extended grep includes meta characters that were added later. The pipe character is also treated as a meta character in extended grep.

To make sure you understand how to use grep to search multiple strings, we suggest creating a file with some text on which we are going to try out a couple of different use cases.

In our case, we named the file sample. In the examples below, we will use grep instead of extended grep. Do not forget to use the backslash before the pipe character.

For example, to search for the words extra and value in the sample. If the same file is in another directory , you need to navigate to that directory or use the full path of the file:. For example, to search for three words, add the desired string of characters followed by a backslash and pipe:. We will use grep in further examples, but you can use whichever syntax you prefer. If you want to find exact matches for multiple patterns, pass the -w flag to the grep command. For example, the output below shows the difference between searching without -w and with it:.

As you can see, the results are different. The first command shows all lines with the strings you used. The second command shows how to grep exact matches for multiple strings.

The output prints only the lines that contain the exact words. Note: Grep offers many functionalities. Learn how to use grep for additional use cases. To avoid missing something when you search for multiple patterns, use the -i flag to ignore letter case. The output shows how the two commands differ.

If you include the -i flag and ignore letter case, the result for multiple matches includes all matches. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Podcast Making Agile work for data science. Stack Gives Back Featured on Meta. New post summary designs on greatest hits now, everywhere else eventually. Related Hot Network Questions. Question feed. Stack Overflow works best with JavaScript enabled.

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