pwd
Print the current working directory.
Script reading, safe guards, text helpers, logging, and review habits.
Read a script header and metadata before execution.
Advanced 02 Shell scripting Script-style outputUse printf to create predictable script output.
Advanced 03 Shell scripting Test guardsUse test commands as script-style guards.
Advanced 04 Shell scripting Basename in scriptsUse basename to report script inputs.
Advanced 05 Shell scripting Dirname in scriptsUse dirname to reason about script paths.
Advanced 06 Shell scripting Sed config previewPreview config text replacement as a script step.
Advanced 07 Shell scripting Awk reportsBuild a small report from fields.
Advanced 08 Shell scripting Cut in scriptsExtract account fields for script-style checks.
Advanced 09 Shell scripting Normalize textNormalize labels before comparing output.
Advanced 10 Shell scripting Tee script logsCapture command output as a script log.
Advanced Checkpoint 11 Shell scripting Xargs reviewUse xargs for safe argument shaping.
Advanced 12 Shell scripting Script execution modeSet executable bits only after review.
Advanced 13 Shell scripting Script diff reviewCompare config snapshots as a script review habit.
Advanced 14 Shell scripting Script checksum reviewHash scripts and compare notes before trusting them.
Advanced 15 Shell scripting Shell scripting checkpointComplete a mini script-review workflow.
Capstone Checkpoint 16 Shell scripting Shebang readingInspect script interpreter declarations before execution.
Admin 17 Shell scripting Set eu reviewRecognize strict-mode style script guards.
Admin 18 Shell scripting Script guard checksCheck required files before script-style work.
Admin 19 Shell scripting Script log captureCapture script-style output into a log file.
Admin 20 Shell scripting Path helper script reviewUse basename and dirname as script building blocks.
Admin 21 Shell scripting Config diff scriptReview config drift with diff and grep.
Admin 22 Shell scripting Argument shape reviewUse xargs only for safe argument shaping.
Advanced 23 Shell scripting Executable bit reviewSet executable mode only after reading a script.
Advanced 24 Shell scripting Checksum before runHash scripts and read notes before trusting them.
Advanced 25 Shell scripting Shell expanded checkpointComplete a script review from guards to logs.
Capstone Checkpoint 26 Shell scripting Script input guardUse test checks to prove required files and directories exist.
Admin 27 Shell scripting Quoted argument reviewPreserve a multi-word value while capturing predictable output.
Admin 28 Shell scripting Predictable output contractCreate machine-readable status lines and verify their shape.
Admin 29 Shell scripting Script path resolutionResolve script paths and report their directory and basename.
Admin 30 Shell scripting Script change reviewCompare configuration snapshots and record a review marker.
Advanced Checkpoint 31 Shell scripting Shell workflow bridgeCheckpoint guards, path handling, output contracts, and change review.
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pwd
Print the current working directory.
echo <text>
Print text or write lab notes with >.
printf <text>
Print formatted training text.
cat <file>
Print text file contents.
head|tail [-n N] <file>
Read the beginning or end of a file.
grep [-i] <text> <file>
Find literal text inside a file.
awk '{print $N}' <file>
Print a whitespace-delimited field.
sed s/old/new/ <file>
Preview simple text substitutions.
cut -d <char> -f <n>
Extract delimited fields from text.
tr a-z A-Z
Transform piped text case.
tee <file>
Write piped text to a lab file and keep it on screen.
xargs echo|basename
Turn piped words into safe command arguments.
diff <left> <right>
Compare two lab text files.
sha256sum <file>
Print a deterministic training checksum.
realpath <path>
Resolve a path to its canonical simulated location.
basename|dirname <path>
Split paths into file and directory parts.
test -e|-f|-d <path>
Check path type in a training-friendly way.
chmod <mode> <path>
Change a simulated numeric permission mode.
stat <path>
Show lab file details.
history
Show recent commands.