DEV Community: Kruti Bhagat

Linux File Handling Commands Cheatsheet

Kruti Bhagat — Wed, 08 Jul 2026 12:37:43 +0000

Linux file handling commands cheatsheet for quick revision.

File Handling

Access Files and Directories

Command	Description
`pwd`	Print working directory
`ls`	List files and directories
`ls -l`	List files with detailed information
`ls -a`	List all files including hidden files
`cd <directory>`	Change to specified directory
`cd ..`	Move to parent directory
`cd ~`	Move to home directory

Create Files and Directories

Command	Description
`touch <filename>`	Create an empty file
`touch <file1> <file2>`	Multiple file creation
`mkdir <directory>`	Create a new directory
`mkdir -p nested/dir`	Create nested directories

Remove Files and Directories

Command	Description
`rm <filename>`	Delete a file
`rm <file1> <file2>`	Delete multiple files
`rmdir <directory>`	Delete an empty directory
`rm -r <directory>`	Delete a directory and its contents
`rm -rf <directory>`	Force delete a directory and its contents

Copy Files and Directories

Command	Description
`cp <source> <destination>`	Copy a file
`cp -r <source_dir> <destination_dir>`	Copy a directory recursively

Move and Rename Files and Directories

Command	Description
`mv <source> <destination>`	Move a file or directory
`mv <oldname> <newname>`	Rename a file or directory

Read and View Files

Command	Description
`cat <filename>`	Display entire file content
`less <filename>`	View file page by page (forward/backward navigation)
`more <filename>`	View file page by page
`head <filename>`	Display first 10 lines
`head -n <number> <filename>`	Display first n lines
`tail <filename>`	Display last 10 lines
`tail -n <number> <filename>`	Display last n lines
`tail -f <filename>`	Monitor file updates in real time

Search Within Files

Command	Description
`grep "<text>" <filename>`	Search for text in a file
`grep -i "<text>" <filename>`	Case-insensitive search
`grep -r "<text>" <directory>`	Search recursively in a directory

File Information

Command	Description
`ls -l`	Display detailed file information
`file <filename>`	Display file type
`stat <filename>`	Display detailed file metadata
`wc <filename>`	Count lines, words, and characters

Find Files

Command	Description
`find . -name "<filename>"`	Find a file by name
`find . -name "*.txt"`	Find all `.txt` files
`which <command>`	Show location of an executable

Disk Usage

Command	Description
`du -sh *`	Display size of files and directories
`df -h`	Display disk usage in human-readable format

View File Permissions

Command	Description
`ls -l <filename>`	View file permissions
`stat <filename>`	View detailed permission and ownership information

Change File Permissions (Symbolic)

Command	Description
`chmod +x <filename>`	Add execute permission
`chmod -w <filename>`	Remove write permission
`chmod u+rw <filename>`	Give owner read and write permission
`chmod g+x <filename>`	Give group execute permission
`chmod o-r <filename>`	Remove read permission from others
`chmod a+r <filename>`	Give read permission to everyone

Change File Permissions (Numeric)

Command	Description
`chmod 755 <filename>`	Owner: rwx, Group: r-x, Others: r-x
`chmod 700 <filename>`	Owner: rwx, Group: ---, Others: ---
`chmod 644 <filename>`	Owner: rw-, Group: r--, Others: r--
`chmod 600 <filename>`	Owner: rw-, Group: ---, Others: ---

Common Linux Permission Values

Octal	Permissions	Meaning
0	`---`	No permissions
1	`--x`	Execute only
2	`-w-`	Write only
3	`-wx`	Write + execute
4	`r--`	Read only
5	`r-x`	Read + execute
6	`rw-`	Read + write
7	`rwx`	Read + write + execute

Change Ownership

Command	Description
`sudo chown <user> <filename>`	Change file owner
`sudo chown <user>:<group> <filename>`	Change owner and group
`sudo chgrp <group> <filename>`	Change group ownership

Vim Editor

Open/Create Files

Command	Description
`vim <filename>`	Open or create a file
`vim`	Open Vim without a file

Vim Modes

Key	Description
`i`	Insert mode (insert before cursor)
`I`	Insert at beginning of line
`a`	Append after cursor
`A`	Append at end of line
`Esc`	Return to Normal mode

Save and Exit

Command	Description
`:w`	Save file
`:q`	Quit Vim
`:wq`	Save and quit
`:x`	Save (if modified) and quit
`ZZ`	Save and quit
`:q!`	Quit without saving

Editing in Vim

Command	Description
`dd`	Delete current line
`yy`	Copy (yank) current line
`p`	Paste below cursor
`P`	Paste above cursor
`x`	Delete current character
`u`	Undo last change
`Ctrl + r`	Redo last undone change

Navigation in Vim

Command	Description
`gg`	Go to beginning of file
`G`	Go to end of file
`:<line_number>`	Go to a specific line
`0`	Go to beginning of current line
`$`	Go to end of current line

Search in Vim

Command	Description
`/text`	Search forward for text
`?text`	Search backward for text
`n`	Next search result
`N`	Previous search result

Chrome's Split View

Kruti Bhagat — Wed, 04 Mar 2026 12:30:11 +0000

Do you ever wonder what more could possibly be added to established products like Chrome or Gmail? Yet new features — like Chrome’s Split View — continue to surprise me, and I’m all for it.

I use the Rectangle window manager app to adjust multiple windows on my screen. But when I have to split the view with 2 Chrome tabs, I often separate those tabs into another Chrome window. With this cool split-view feature, I get to stay in the same Chrome window and have only specific tabs split side by side.

I was probably living under a rock as people are talking about this since Dec 2025, and I only discovered it by accident today while I was copying my post to dev.to. Either way, I already see myself using it every day.

To have a split view, select the two tabs and right-click. Select "Add tab to new split view" option.

And you have merged tabs!

You can resize the frames like this

If you don't see this option, then you likely have this feature disabled. Type chrome://flags/#side-by-side in new tab and enable the split view feature.

Checkout the official blog post here: https://blog.google/products-and-platforms/products/chrome/chrome-productivity-improvements/

SQL Cheatsheet

Kruti Bhagat — Wed, 04 Mar 2026 11:40:54 +0000

Here's a cheat sheet to quickly review all SQL queries before an interview.

TABLE Queries

CREATE TABLE table_name (column1 datatype, column2 datatype, ... );

DROP TABLE table_name;

ALTER TABLE table_name ADD column_name datatype;

INSERT INTO table_name (column1, column2)
VALUES (value_or_expr1, value_or_expr2);

SELECT Queries

SELECT * FROM table_name;

SELECT DISTINCT column_name1, column_name2 FROM table_name;

SELECT column_name1 FROM table_name
ORDER BY column_name2 ASC / DESC; /* (by default it is ascending if
you don't write DESC) */

SELECT column_name1 FROM table_name WHERE column_name2 BETWEEN x AND y;
SELECT column_name1 FROM table_name WHERE column_name2 NOT BETWEEN x AND y;

SELECT column_name1 FROM table_name WHERE column_name1 LIKE "%XYZ%";
SELECT column_name1 FROM table_name WHERE column_name1 NOT LIKE "%XYZ%";

SELECT column_name FROM table_name
ORDER BY column_name1
LIMIT number_of_rows
OFFSET num_offset; /* The LIMIT will reduce the number of rows to
return, and the optional OFFSET will specify where to begin counting
the number rows from. */

SELECT table1_column, table2_column, …
FROM table1
INNER/LEFT/RIGHT/FULL JOIN JOIN table2 
    ON table1.id = table2.matching_id
WHERE condition(s)
ORDER BY table1_column, … ASC/DESC
LIMIT num_limit OFFSET num_offset;

SELECT AGG_FUNC(column_or_expression) AS aggregate_description, …
FROM table_name
WHERE constraint_expression
GROUP BY column_name

AGG_FUNC -> COUNT(*), COUNT(column), MIN(column), MAX(column), AVG(column), SUM(column)

SELECT group_by_column, AGG_FUNC(column_expression) AS aggregate_result_alias, …
FROM mytable
WHERE condition
GROUP BY column
HAVING group_condition;

A complex SQL SELECT query combining joins, aggregation, filtering, sorting, and pagination would look something like this.

SELECT DISTINCT column, AGG_FUNC(column_or_expression), …
FROM mytable
    JOIN another_table
      ON mytable.column = another_table.column
    WHERE constraint_expression
    GROUP BY column
    HAVING constraint_expression
    ORDER BY column ASC/DESC
    LIMIT count OFFSET COUNT;

I hope this helps you with interview prep as it does to me. I find https://sqlbolt.com/ super helpful if you want to learn SQL queries in depth. Thanks!

Git Cheatsheet

Kruti Bhagat — Tue, 03 Mar 2026 23:07:06 +0000

This cheatsheet lists commands we use to submit a PR (pull request) to a GH (github) repo. It is mainly for my reference, but if you found it helpful, leave a like!

git checkout -b *branch_name* Creates and switches to the new branch

git checkout - switch to the previous branch

git status to check files that have been changed

git diff shows the code difference in the terminal

git add . to stage all files for commit

git commit -m "*commit message goes here*" to commit the changes

You can use git commit and then you’ll be redirected to either nano or vi editors to enter the commit message.

For nano editor: Type message, ^X to exit the file and y to save the file.

For vi editor: i for insert mode, type the message and then ESC. :wq to save text and exit, or :q to simply exit

git push --set-upstream origin *branch_name* to push the branch and changes. git push works too, but you have to mention the branch_name the first time you push changes.

Revert commits before they are pushed to GH repo:

Soft Reset – Changes stay, commit is reverted
- git log (Shows commit log. We find the previous commit hash with it.)
- git reset --soft ***previous commit hash***
- git reset —soft HEAD^1
Hard Reset – Changes and commit both are reverted
- git reset --hard ***previous commit hash***
- git reset —hard HEAD^1

Revert commits after they are pushed to the GH repo:

git revert ***commit hash*** to revert the commit that was pushed. This will revert the commit locally. This should be followed by git push so that the changes are reverted on GH repo.

git bisect checks what broke between specific commits and narrows down the search between a commit range.

Reset the local branch to match the remote branch:

git fetch origin fetches the latest changes from the remote branch
git reset --hard origin/*branch_name* resets local branch
git clean -f -d to delete untracked files
git pull to pull all the contents from the repo