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--- bash [2023/01/17 14:19] – created roger
+++ bash [2024/11/17 12:59] (current) – external edit 127.0.0.1
@@ Line 3: / Line 3: @@
 Useful Bash code, with no particular order
+===== Add safeguards on every script =====
+At the top of the file, always start your scripts with:
+<code bash>
+set -euo pipefail
+</code>
+  * ''-e'': The -e option will cause a bash script to exit immediately when a command fails.
+  * ''-o pipefail'': This particular option sets the exit code of a pipeline to that of the rightmost command to exit with a non-zero status, or to zero if all commands of the pipeline exit successfully.
+  * ''-u'': This option causes the bash shell to treat unset variables as an error and exit immediately.
+More info: https://vaneyckt.io/posts/safer_bash_scripts_with_set_euxo_pipefail/
+===== Read passwords with feedback on a script =====
+<code bash>
+unset password
+charcount=0
+prompt="Enter your password: "
+while IFS= read -p "$prompt" -r -s -n 1 char
+do
+    if [[ $char == $'\0' ]]
+    then
+        break
+    fi
+    if [[ $char == $'\177' ]] ; then # Backspace support
+        if [ $charcount -gt 0 ] ; then
+            charcount=$((charcount-1))
+            prompt=$'\b \b'
+            password="${password%?}"
+        else
+            prompt=''
+        fi
+    else
+        charcount=$((charcount+1))
+        prompt='*'
+        password+="$char"
+    fi
+done
+</code>