# LS COMMAND: TASK-BASED CHEATSHEET
====================================

```
 _     _____   _____                                          _ 
| |   / ____| / ____|                                        | |
| |  | (___  | |     ___  _ __ ___  _ __ ___   __ _ _ __   __| |
| |   \___ \ | |    / _ \| '_ ` _ \| '_ ` _ \ / _` | '_ \ / _` |
| |_______) || |___| (_) | | | | | | | | | | | (_| | | | | (_| |
|______\____/ \_____\___/|_| |_| |_|_| |_| |_|\__,_|_| |_|\__,_|
```

## EVERYDAY TASKS
----------------

### 🔍 FINDING WHAT YOU NEED
Find hidden configuration files:
  $ ls -a ~/.config

List only directories:
  $ ls -d */ 
  $ ls -l | grep "^d"

Find executable files:
  $ ls -l | grep "^-..x"

Find recently modified files:
  $ ls -lt | head

Find largest files:
  $ ls -lS | head

### 📊 ANALYZING DISK USAGE
Quick directory size analysis:
  $ ls -lh
  $ ls -la --block-size=M

Compare file count in directories:
  $ for i in */; do echo -n "$i: "; ls -A "$i" | wc -l; done

### 🔒 SECURITY CHECKS
Check for world-writable files:
  $ ls -l | grep "^.\{7\}w"

Examine file permissions in bulk:
  $ ls -l | awk '{print $1, $9}'

Check ownership of files:
  $ ls -l | grep "username"

Find SUID/SGID files:
  $ ls -l | grep "^.....s"

### 📝 DOCUMENTATION & REPORTING
Create file inventory:
  $ ls -la > directory_inventory.txt

Generate CSV listing:
  $ ls -l | awk 'NR>1 {print $9","$5","$6" "$7}' > files.csv

File count by extension:
  $ ls -l | grep -E "\.[a-z]{3}$" | awk '{print $NF}' | sed 's/.*\.//' | sort | uniq -c


## SPECIALIZED SCENARIOS
----------------------

### 🔄 BACKUP VERIFICATION
Compare two directories:
  $ diff <(ls -la dir1) <(ls -la dir2)

Verify timestamps after restoration:
  $ ls -lt --time=ctime /backup/dir

### 🐋 CONTAINER & VIRTUALIZATION
List files with context (containers):
  $ ls -laZ /var/lib/docker

Size check before image build:
  $ ls -lah --block-size=M ./docker-context

### ☁️ CLOUD OPERATIONS
Check upload candidates by size:
  $ ls -laSh | head -20

Verify download completion:
  $ ls -la --time-style=full-iso ./downloads

### 🔧 TROUBLESHOOTING
Find zero-length files:
  $ ls -l | grep " 0 "

Check for broken symlinks:
  $ ls -l | grep -E "^l.*->"

List inode information (filesystem issues):
  $ ls -li

Examine extended attributes:
  $ ls -la@ # macOS
  $ ls --context # Linux with SELinux


## POWER USER TECHNIQUES
----------------------

### 🧰 ADVANCED FORMATTING
Custom time format:
  $ ls -l --time-style="+%Y-%m-%d %H:%M:%S"

Custom columns:
  $ ls -l | awk '{print $9 "\t" $5 "\t" $3}'

JSON output (with helper):
  $ ls -la | awk 'BEGIN {print "["} NR>1 {print "  {\"name\":\"" $9 "\", \"size\":" $5 "},"}  END {print "]"}' | sed 's/,]/]/'

### 🔍 COMPLEX FILTERING
Files modified in last 24 hours:
  $ find . -type f -mtime -1 -exec ls -l {} \;

Files not accessed in 90+ days:
  $ find . -type f -atime +90 -exec ls -l {} \;

Only certain file types:
  $ ls -l | grep -E "\.(jpg|png|gif)$"


## 🥇 ONE-LINERS FOR SPECIFIC TASKS
---------------------------------
Disk usage by file type:
  $ ls -la | grep -v ^d | awk '{print $9}' | grep -o "\.[^.]*$" | sort | uniq -c | sort -nr

Find duplicate files (by size, rough check):
  $ ls -l | awk '{print $5,$9}' | sort -n | uniq -D -f1

Extract creation dates for timeline:
  $ ls -la --time=birth | awk '{print $6, $7, $8, $9}'

Build project file manifest:
  $ find . -type f -name "*.py" | sort | xargs ls -l | awk '{print $5, $9}' > manifest.txt


## 🔀 COMBINING WITH OTHER TOOLS
-----------------------------
With xargs:
  $ ls -1 *.log | xargs wc -l

With watch (monitor directory):
  $ watch -n 1 'ls -la /var/log'

With stat (detailed info):
  $ ls -1 | xargs stat --format="%n: %s bytes, %y"

With for loops:
  $ for file in $(ls *.txt); do echo "Processing $file"; cat "$file" | wc -l; done


## 🔧 ENVIRONMENT CUSTOMIZATION
----------------------------
Customize ls colors:
  $ export LS_COLORS="di=1;34:fi=0;37:ln=1;36:pi=1;33:so=1;35:bd=1;33:cd=1;33:ex=1;32"

Create smart aliases:
  $ alias lm='ls -la | more'
  $ alias lsize='ls -laSh | head -20'
  $ alias lnew='ls -ltr | tail'
  $ alias lold='ls -ltr | head'

Make it portable (POSIX compliance):
  $ ls -1rt # Works on most Unix-like systems


## 🔴 COMMON GOTCHAS & SOLUTIONS
-----------------------------
"ls: Argument list too long"
  → Use find instead:
    $ find . -type f -name "*.log" -exec ls -la {} \;

"Permission denied" everywhere:
  → Check current directory permissions:
    $ ls -ld .

Hidden files confusion:
  → Remember -a shows dot files, but -A excludes . and ..
    $ ls -A # Show hidden files, but not . and ..

Multi-user conflicts:
  → Check file owner vs current user:
    $ ls -la | grep $(whoami)