AWK Linux/Unix ka ek powerful text processing aur pattern scanning tool hai. Iska use text files ko search, filter, format, analyze aur report generate karne ke liye kiya jata hai. Command line par bade logs aur files ko parse karne ke liye ye sabse zyada pasand kiya jaane wala tool hai.

AWK ka naam iske original creators ke surname se lekar rakha gaya hai:

• A – Alfred Aho
• W – Peter Weinberger
• K – Brian Kernighan

AWK Ka Basic Syntax

AWK ko use karne ke do mukhya tarike hain:

awk 'pattern { action }' filename

Ya phir bina kisi pattern ke sirf action chalane ke liye:

awk '{ action }' filename

• Pattern: Yeh nirdeshit karta hai ki kis specific line ya condition par action perform karna hai.
• Action: Yeh batata hai ki select ki gayi lines ke sath kya task execute karna hai (jaise print karna).

Example File Setup

Maan lijiye hamare paas ek demo text file hai jiska naam employees.txt hai:

AWK Practical Examples

Example 1: Puri File Print Karna

Bina kisi rules ke poori file ko output me dekhne ke liye print ka use karein:

awk '{print}' employees.txt

Example 2: First Column Print Karna

AWK har line ko automatically spaces ke basis par parse karta hai. Pehla column nikalne ke liye $1 use karein:

awk '{print $1}' employees.txt

Note: $1 yani Pehla column, $2 Yani Doosra column, aur isi tarah aage kaam karta hai.

Example 3: Multiple Columns Print Karna

Do ya do se zyada columns ko ek sath comma lagakar print kiya ja sakta hai:

awk '{print $1,$3}' employees.txt

Example 4: Line Number (Row Number) Print Karna

NR ek internal variable hai jo line number handle karta hai, aur $0 poori line ke data ko specify karta hai:

awk '{print NR,$0}' employees.txt

Important Built-in Variables Table

AWK me pehle se bani hui commands hoti hain jo hamara kaam aasan karti hain:

Example 5: Sirf IT Department Ka Data Filter Karna

Kisi string specific search ke liye string comparison lagaya jata hai:

awk '$2=="IT"' employees.txt

Example 6: Greater Than Condition (Salary > 6000)

Aap mathematical conditions bhi laga sakte hain:

awk '$3 > 6000' employees.txt

Example 7: Field Separator Badanna (CSV Files Ke Liye)

Agar file comma-separated values (CSV) format me hai, to use process karne ke liye -F filter use kiya jata hai:

awk -F "," '{print $1,$2}' employees.csv

Calculations Aur Reports Generator

Example 8: Total Salary Calculate Karna

AWK variables bana kar operations kar sakta hai. END block file ke bilkul aakhir me chalta hai:

awk '{sum += $3} END {print sum}' employees.txt

Example 9: Average Salary Nikalna

awk '{sum += $3} END {print sum/NR}' employees.txt

Example 10: BEGIN aur END Blocks Ka Use

awk '
BEGIN {print "Employee Report"}
{print $1,$3}
END {print "Report Finished"}
' employees.txt

AWK vs GREP vs SED

Cyber Security Aur Log Analysis Mein AWK Ka Use

Users ki list extract karna:

cat /etc/passwd | awk -F ":" '{print $1}'

System me chal rahe listening ports dekhna:

ss -tuln | awk '{print $5}'

Auth Logs me se Failed logins trace karna:

awk '/Failed/ {print}' auth.log

Access Logs se Target IP addresses filter out karna:

awk '{print $1}' access.log

Conclusion

AWK Linux ecosystem ka ek behad shaandar aur tezi se kaam karne wala tool hai. Agar aap Linux Administration, DevOps, Ethical Hacking ya Security Analytics ka career target kar rahe hain, to AWK script patterns ko samajhna aapke kaam ko bohot zyada efficient bana dega.