Bash is necessary for quick tasks and gluing commands together.
Variables and control flow:
#!/bin/bash
for file in *.log; do
count=$(grep -c ERROR "$file")
echo "$file: $count errors"
done
Useful constructs:
$?: Exit code of last command$(command): Command substitution|: Pipe output to next command&&/||: Conditional execution
Text processing:
grep: Filter linesawk: Column extractionsed: Stream editingsort | uniq -c: Count occurrences
Interview tip: Know when Bash is appropriate (quick, simple tasks) vs when Python is better (complex logic, error handling).