Tag: scripting

Unquoted bash variables split on IFS and quietly break loops, file ops, and filenames with spaces. Here's why it happens and how to always quote right.

Bash has built-in string operations: substring extraction, find-replace, case conversion, and trimming. You don't need sed for basic text work.

set -e looks bulletproof, but it slips right through pipes, command substitution, and conditionals. The bash gotchas that bite at 2 AM, and how to fix them.

Bash has built-in arithmetic. You don't need bc for 90% of math. Here's how to do it right.

set -euo pipefail makes your bash scripts fail fast instead of silently. Here's what each flag does and why they matter.

awk is perfect for parsing logs. 5 patterns for filtering, summing, counting, splitting fields, and reformatting, no Perl or Python required.

jq is JSON on the command line. Here are 5 one-liners that actually solve real problems: filtering, extracting, transforming, combining, and debugging.

xargs and while read both loop over input, but they handle arguments, signals, and performance differently. Here's when to use each.

Practical find command examples: -mtime, -newer, -type, -exec vs xargs, -not, size filters. The patterns you google every time.

Write bash scripts that don't silently fail, set -euo pipefail, error handling, input validation, and logging patterns for production scripts.

By default bash history is lost across multiple terminal sessions. Fix it with HISTAPPEND and PROMPT_COMMAND so nothing gets overwritten.

Something's squatting on port 8080 and you need to know what. ss, netstat, and lsof one-liners to find the PID behind a port fast.