To loop through the files in a directory in Unix, you can use a for loop in a shell script.
Here is an example of a for loop that loops through the files in the /tmp directory:
for file in /tmp/* do echo "$file" done
This for loop will loop through all of the files in the /tmp directory, and the echo command will print the name of each file.
You can use any command or series of commands inside the do and done blocks to process the files. For example, you can use the cat command to print the contents of the files, or the mv command to move the files to a different directory.
You can also use variables inside the for loop to process the files. For example, you can use the $file variable to refer to the current file being processed in the loop.
For more information about for loops and other shell script constructs, you can consult the documentation for your specific Unix or Linux system.