Bash Commands

pwd -------------------Present Working Directory path
ls -------------------- To view directories and files in a folder
ls -R ----------------- To view subdirectories of directories.
ls -t
ls -l ------------------To view permissions, last modified date, size in bytes of particular folder.
ls -lt
ls -la -----------------To view all items including hidden items.
ls -lRa
ls -lr -----------------shows in reverse order.
ls -s ------------------To view size.
ls *.js ----------------To view all the js files in that folder.
ls Zoo* ----------------To view all the files with "Zoo" in its name.
ls .. ------------------list all directories and folder.
cd ---------------------------Go to
cd .. ------------------------Go to previously directory.
cd ../../ --------------------Go back twice.
touch ------------------------To create a file. {touch a.js}
cat --------------------------To view what is inside in a file. {cat a.js}
cat > a.txt ------------------To write something in a file. ctrl + D to save and exit. ctrl + C to exit.
cat >> a.txt
mkdir ------------------------------create a directory of name test. {mkdir test}
mkdir test && cd test --------------create a new directory and go inside that directory.
mkdir -p ---------------------------To create directory inside directory. {mkdir -p frontend/scripts}
mv ---------------------------------To move files. {mv script.js runtime_script.js}
mv filepath/newname ----------------To rename a file.
cp ---------------------------------To copy files {cp filepath new filepath}
cp -r ------------------------------To copy a directory.
rm filename ------------------------To delete a file.
rm -r folderpath -------------------To delete a folder.
chmod ugo-rwx ---------------------------To add permission to a file.
chmod -R ugo-rwx ------------------------To add permission to a folder.
chmod u+x filename
chmod g+wx filename
chmod u-x filename

1-x, 2-w, 4-r

chmod 664 folder name
echo 'Hello World'---------------------------To display a certain message.
head filename -------------------------------View us the first 10 rows of a file.
tail filename -------------------------------View us the last 10 rows of a file.
head -20 filename ---------------------------View the first 20 rows of a file. same goes with tail.
tail -n +25 filename | head -n +5 -----------To view custom rows.
wc filename ---------------------------------To view linecount, wordcount, charactercount of a file.
grep "one" filename ------------------where "one" has been used in the file.
grep "one" filename | wc -l ----------how many times "one" has been used in the file.
grep -c "one" filename ---------------how many times "one" has been used in the file.
grep -h "one" filename ---------------where "one" has been used in the file. (case sensitive)
grep -hi "one" filename --------------where "one" has been used in the file. (not case sensitive)
grep -hir "one" directoryname --------where "one" has been used in the folder.
grep -hin "one" filename -------------where "one" has been used in the file inc line numbers. (not case sensitive)
grep -hinw "one" filename ------------where "one" has been used inside a word also individually. {colone, one, One} (case sensitive)
grep -o "one" filename ---------------only gives us the matched part.
grep -w "one" filename ---------------where "one" has been used in the file.
history ------------------------------to view all the command that i've used.
bash filename
grep "ERROR" filename ----------------will view all the error messages in that file.
grep -v "INFO" filename
grep -A 5 ERROR filename -------------to view rows after the occurance of ERROR text in a file
grep -B 5 ERROR filename -------------to view rows before the occurance of ERROR text in a file
grep -C 5 ERROR filename -------------to view rows before and after the occurance of ERROR text in a file.
sed -n '/ERROR/ p' filename ------------------to print lines with ERROR text.
sed 's/ERROR/CRITICAL' filename --------------Replace ERROR with CRITICAL in the file.
sed -ibackup 's/ERROR/CRITICAL/' filename ----Create a backup of the file.
sed '3 s/CRITICAL/VERYCRITICAL/' filename ----Replace CRITICAL with VERYCRITICAL in line number 3.
sed '3,5 s/ERROR/CRITICAL/' filename ---------Replace CRITICAL with VERYCRITICAL in line number 3 to line number 5.
sed -n '3,/ERROR/ p' filename
awk '/ERROR/{print $0}' filename -------------------------to print lines with ERROR text.
awk '{gsub(/ERROR/, "CRITICAL")}{print}' filename---------Replace ERROR with CRITICAL in the file.
awk 'BEGIN {print "LOG SUMMARY\n--------------"} {print} END {print "--------------\nEND OF LOG SUMMARY"}' filename ---------add text in the beginning and ending of a file.
awk '{print $1, $2}' filename ----------------------------Print 1st and the 2nd column of the data (file).
awk -F "," '{print $1, $2}' filename
awk '{count[$2]++} END {print count["ERROR]}' filename ---Count the occurance of ERROR in second column of the file.
awk '{ if ($1 > 1598863888 ) {print $0} }' log.txt -------view the rows after 1598863888 in first column.

Git

git status to check status
git init to initialized git

Commit

git add {FILE_NAME} or for all git add . to tracking or staging area
git commit -m “{MESSAGE}” to make file in commit stage
git commit -am “{MESSAGE}” shortcut to add and commit.
git log to logs all commits
git log —oneline gives logs in one line

Atomic Commits

Keep commits centric to one feature, one component or on fix
Present or past commit msg depends {Present tense, imperative} give order to code base don’t care
git config —global user.name “Bashar Khan” and user.email “basharkhan7776@gmail.com”
.gitignore generator to generate that project

Branch

git branch show the current branch name
git branch -M main to rename to main (mainly in open sourced)
git branch {BRANCH_NAME} create new branch
git checkout {BRANCH_NAME} or git switch {BRNCH_NAME} switch branch
git checkout -b {BRANCH_NAME} or git switch -c {BRNCH_NAME} create and switch branch

Merging

git checkout master
git merge {BRACNH_NAME}

⚡ After merging it may give Conflict , which may be resolve in vs code

git diff --staged to see the difference after stage file
git diff {BRANCH1} {BRANCH2} also gives the diff b/w branches
git diff {LOG_ID1} {LOG_ID1} also gives the diff b/w log id's

Stash

git stash change branch without commit. (like temp storage)
git stash pop to bring back prev code.

More Command

git checkout {HASH} go to that commit files.
git switch main re-attach to Head.
git checkout HEAD~2 look at 2 commit prior
git restore {FILE_NAME} get back to last commit version

Rebase

🚫Never run this command in main or master branch

git rebase master join branch to master or other branch and clean up prev history

⚡ Never rebase commits that have shared.

→ Push to Github → Never rebase

GitHub

→ Github is the service to host things online.

git clone {URL} to clone any repo.
git remote -v list of remote repo in git.
git remote {NAME} {URL} add remote file to locally.
git remote origin https://www.github.ksjnfannsdf.git mainly use in github.
git remote add origin https://www.github.ksjnfannsdf.git mainly use in github.
git remote rename {OLD_NAME} {NEW_NAME} to rename remote file.
git remote remove {NAME} to remove remote file.
git push {REMOTE_NAME} {BRANCH_NAME} push file to remote from branch.
git push origin main push only one time
git push -u origin main or git push --set-upstream origin main setup an upstream that allow u to run future git push command and push code directly to github.

Open Sourced Contributions

First fork in repository so admin make eye on you.
Clone to your machine.
Make another Branch in git, don't interrupt main
Done your work and the Push that branch into remote
Back to GitHub and u well see Create Pull Request in site
Add Title and Description (markdown syntax)
Can PR to main or can other branch

Problems in connecting in github with WSl :

→ In PR it ask username and password.

→ Make classic token from GitHub profile Setting > Developers Setting > Token(Classic).

→ Make one token for auth save it for later.

→ In WSL after PR, enter username and in pass past saved token.

Reference

https://www.youtube.com/watch?v=zTjRZNkhiEU&list=WL

https://git-scm.com/doc

https://docs.github.com/en