Linux File Management – Copy, Move, Delete and View Files (cp, mv, rm, cat, less, grep, wc)

Introduction

In VLSI verification and RTL design, file management is a daily task — moving testbenches, creating backups, cleaning log files, or searching through massive simulation outputs.
This tutorial covers essential Linux commands to copy, move, delete, and search files efficiently.

1. Copying Files and Directories – cp

To make a copy of a file:

cp file1 file2

Example:

cp science.txt backup.txt

This creates a new file named backup.txt with the same content as science.txt.

To copy directories recursively (including subfolders):

cp -R dir1 dir2

💡 Example:
 cp -R rtl backup_rtl — copies your RTL folder with all files.

2. Moving and Renaming Files – mv

Move or rename files:

mv file1 file2

If file2 doesn’t exist → it renames the file.
If file2 is a directory → it moves the file inside that directory.

Examples:

mv science.txt ~/unixstuff/backups/

mv report.log old_report.log

📘 Use Case: Renaming simulation logs after each run (e.g., sim_v1.log → sim_final.log).

3. Removing Files and Directories – rm, rmdir

To delete a file:

rm filename

To remove an empty directory:

rmdir dirname

To delete a directory and all its contents (use with care):

rm -r dirname

⚠️ Caution: There is no recycle bin in Linux. Once deleted, it’s gone.

4. Displaying File Contents

cat

Display the entire file:

cat science.txt

less

View a file page-by-page (recommended for long logs):

less science.txt

Use:

Space → next page
q → quit

head

View the first 10 lines (default):

head science.txt

To see 5 lines:

head -5 science.txt

tail

View the last 10 lines:

tail science.txt

To view last 15 lines:

tail -15 science.txt

💡 EDA Tip: Use tail -f sim.log to monitor a simulation log live while running.

5. Searching Inside Files – grep

Search for a keyword:

grep science science.txt

Ignore case:

grep -i science science.txt

Count matching lines:

grep -c science science.txt

Show non-matching lines:

grep -v science science.txt

Highlight matches:

grep --color -i "error" sim.log

💡 Real-World Example: Quickly locate simulation errors:

grep --color -i "uvm_error" sim.log

6. Counting Words, Lines, and Characters – wc

Command	Description
wc -l file	Count lines
wc -w file	Count words
wc -m file	Count characters

Example:

wc -l sim.log

This tells you how long your log file is — handy when checking if the simulation completed fully.

Summary Table

Command	Description
cp file1 file2	Copy file1 to file2
cp -R dir1 dir2	Copy entire directory
mv file1 file2	Move or rename file
rm file	Remove a file
rmdir dir	Remove empty directory
rm -r dir	Remove directory recursively
cat file	Display file content
less file	View file page by page
head file	Show first few lines
tail file	Show last few lines
grep keyword file	Search keyword inside file
wc file	Count words, lines, characters

Practice Tasks

Copy a file named pcie_tlp.sv into a backup directory using cp.
Rename it as pcie_tlp_v2.sv using mv.
Delete any temporary directory with rm -r tempdir.
Search for “UVM_ERROR” in your simulation log with grep –color.
Count the total number of transactions logged using wc -l txn_log.txt.

Real-World Scenario

When debugging simulations:

Use grep -i error *.log to find failing runs.
Use tail -f vcs.log to track progress live.
Use cp and mv to organize multiple test iterations neatly.

These simple commands can save hours during regression analysis.