How to use the grep -e command in Linux?

In Linux, the grep -e command is used to search for specified patterns in a file, allowing for multiple patterns to be searched.

The basic grammar is as follows:

grep -e pattern1 -e pattern2 file

pattern1 and pattern2 are the patterns to be searched, and file is the name of the file to be searched.

Here are some examples:

1. Hi
2. The entire planet.

grep -e hello -e world file.txt

1. I could only find one option.
2. pub

grep -e foo -e bar file.txt

1. The alphabet.

grep -e abc file1.txt file2.txt file3.txt

1. Calm down, there’s no need to get so worked up.

grep -e "^[A-Z]" file.txt

1. hi
2. planet

grep -e hello -e world -v file.txt

The examples provided above are just basic usages of the grep -e command. You can find more advanced usages and options in the help documentation for the grep command (man grep).