Final answer:
To evaluate the contents of a file and find lines that match a regular expression, the grep command is used in Unix-like operating systems.
Step-by-step explanation:
If you want to evaluate the contents of a file and see the lines that match a regular expression, the command that should be used is grep. The grep command, which stands for "global regular expression print," is commonly used in Unix-like operating systems to search through text. You can use it by typing grep 'pattern' filename, where 'pattern' is the regular expression you're looking for and 'filename' is the file you're searching in. For more advanced searches, grep can be used with options like -i to ignore case or -E for extended regular expressions.
To evaluate the contents of a file and see the lines that match a regular expression, you can use the grep command in the terminal. The syntax of the grep command is as follows:grep 'regular_expression' file_nameFor example, if you have a file named 'text.txt' and you want to find all lines that contain the word 'apple', you can use the command:grep 'apple' text.txt.