How to search in multiple files?

To search in multiple files using grep, you can specify multiple filenames or use wildcards. Here are a few methods:

1. Specify Multiple Files: You can list multiple files separated by spaces:

   grep 'pattern' file1 file2 file3
   

2. Using Wildcards: You can use wildcards to search in all files of a certain type. For example, to search for "pattern" in all .txt files in the current directory:

   grep 'pattern' *.txt
   

3. Search Recursively: To search through all files in a directory and its subdirectories, use the -r option:

   grep -r 'pattern' directory/
   

4. Search in All Files: To search in all files in the current directory:

   grep 'pattern' *
   

Example

To search for the word "error" in all .log files:

grep 'error' *.log

Feel free to ask if you need more examples or further clarification!