svieira · March 20, 2024 06:08 · Mar 20, 2024 · Mar 20, 2024 · Apr 5, 2023 · Apr 5, 2023
diff --git a/script-example.sh b/script-example.sh
@@ -47,9 +47,9 @@ while [ "${1+defined}" ]; do
     -d|--option-d) option_d=on;;
     # Allow getopts-style collections of short args
     # This will allow -de and -ed to both parse correctly
-    -d*) set -- "-d" "-${1##-d}" "$@";;
+    -d*) _rest="${1##-d}"; set -- "-d" "-$_rest" "$@";;
     -e|--option-e) option_e=on;;
-    -e*) set -- "-e" "-${1##-e}" "$@";;
+    -e*) _rest="${1##-e}"; set -- "-e" "-$_rest" "$@";;
     *) echo "Unknown option $1" >&2 && exit 1;;
   esac
   shift

diff --git a/script-example.sh b/script-example.sh
@@ -31,7 +31,7 @@ function opt() {
   echo "-$1?(=*)|--$2?(=*)"
 }
 
-
+# See https://argbash.dev/ for more patterns
 while [ "${1+defined}" ]; do
   case $1 in
     -h|--help) echo "$HELP" && exit 0;;
@@ -44,6 +44,12 @@ while [ "${1+defined}" ]; do
     fi;;
     # Using code to define actual pattern (requires shopt -s extglob)
     @($(opt c chatty))) echo "Will chat now" && exit 0;;
+    -d|--option-d) option_d=on;;
+    # Allow getopts-style collections of short args
+    # This will allow -de and -ed to both parse correctly
+    -d*) set -- "-d" "-${1##-d}" "$@";;
+    -e|--option-e) option_e=on;;
+    -e*) set -- "-e" "-${1##-e}" "$@";;
     *) echo "Unknown option $1" >&2 && exit 1;;
   esac
   shift

diff --git a/script-example.sh b/script-example.sh
@@ -27,17 +27,23 @@ HELP
 option_a=
 option_b="$SOME_SYSTEM_VARIABLE"
 
+function opt() {
+  echo "-$1?(=*)|--$2?(=*)"
+}
+
+
 while [ "${1+defined}" ]; do
   case $1 in
     -h|--help) echo "$HELP" && exit 0;;
-    -a?(=*)|--option-a?(=*)) if [[ "$1" = *=* ]]; 
-      then option_a="${1#*=}";
-      else option_a="$2"; shift;
-    fi;;
+    # Simple options
+    -a|--option-a) option_a="$2"; shift;
+    # Options that support being called with =
     -b?(=*)|--option-b?(=*)) if [[ "$1" = *=* ]];
       then option_b="${1#*=}";
       else option_b="$2"; shift;
     fi;;
+    # Using code to define actual pattern (requires shopt -s extglob)
+    @($(opt c chatty))) echo "Will chat now" && exit 0;;
     *) echo "Unknown option $1" >&2 && exit 1;;
   esac
   shift

diff --git a/script-example.sh b/script-example.sh
@@ -1,5 +1,7 @@
 #!/usr/bin/env bash -f
 
+shopt -s extglob
+
 SCRIPT_NAME=`basename $0`
 
 read -rd '' HELP << HELP
@@ -28,9 +30,17 @@ option_b="$SOME_SYSTEM_VARIABLE"
 while [ "${1+defined}" ]; do
   case $1 in
     -h|--help) echo "$HELP" && exit 0;;
-    -a|--option-a) option_a=$2; shift;;
-    -b|--option-b) option_b=$2; shift;;
+    -a?(=*)|--option-a?(=*)) if [[ "$1" = *=* ]]; 
+      then option_a="${1#*=}";
+      else option_a="$2"; shift;
+    fi;;
+    -b?(=*)|--option-b?(=*)) if [[ "$1" = *=* ]];
+      then option_b="${1#*=}";
+      else option_b="$2"; shift;
+    fi;;
     *) echo "Unknown option $1" >&2 && exit 1;;
   esac
   shift
-done
+done
+
+echo "$option_a and $option_b"
diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -5,7 +5,7 @@ done
 
 # Reading a file line by line
 while read var1 var2 etc; do 
-	perform --commands --with $var1 $var2 $etc
+  perform --commands --with $var1 $var2 $etc
 done < some-file.ext
 
 # The for loop with test syntax

diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -1,6 +1,6 @@
 # Looping per line of input
 some | command | sequence | while read var1 var2; do
-
+  # something here
 done
 
 # Reading a file line by line
@@ -10,11 +10,11 @@ done < some-file.ext
 
 # The for loop with test syntax
 for f in *; do 
-    if [[ -d "$f" ]]; then
-        pushd "$f";
-        echo "Do work";
-        popd;
-    fi; 
+  if [[ -d "$f" ]]; then
+    pushd "$f";
+    echo "Do work";
+    popd;
+  fi; 
 done
 
 # Test for a pattern match
@@ -27,5 +27,12 @@ cat <(what magic is this?)
 # http://unix.stackexchange.com/questions/99423/appending-to-same-array-in-various-loops-only-last-values-remain-bash-4
 some_array=()
 while some test; do
-    some_array+=("$some_variable")
-done < <(some command producing output)
+  some_array+=("$some_variable")
+done < <(some command producing output)
+
+# if __name__ == '__main__': equivalent
+if [[ ${BASH_SOURCE[0]} != $0 ]]; then
+  # We were sourced, not run
+else
+  # We are being run, go, go, go!
+fi
diff --git a/commands.sh b/commands.sh
@@ -0,0 +1,15 @@
+# Useful command sequences
+
+# Find the first command that is defined
+# For example, this uses the GNU brew-installed utilities before the normal readline on Mac
+# while on a system without it (or Linux it will use the normal readline)
+type -p greadlink readlink | head -1
+
+# Alter a remote's URL
+git remote -v | cut -d' ' -f 1 | cut -f 1-2 | sed 's/something/something-else/g' | xargs -t -n 2 git remote set-url;
+
+# Run sed on a set of files containing a pattern
+grep -rl matchstring somedir/ | xargs sed -i 's/string1/string2/g'
+
+# Run sed with alternative delimiters (any character will work)
+sed 's_http://some/url_http://some/replacement_g'
diff --git a/script-example.sh b/script-example.sh
@@ -0,0 +1,36 @@
+#!/usr/bin/env bash -f
+
+SCRIPT_NAME=`basename $0`
+
+read -rd '' HELP << HELP
+$SCRIPT_NAME - what the script does
+
+Usage:
+
+$SCRIPT_NAME
+  [-a|--option-a A]             - the first option
+                                  (default: some sensible default)
+  [-b|--option-b B]             - another option
+                                  Falls back on \$SOME_SYSTEM_VARIABLE
+  positional-args ...           - A longer description
+                                  spanning several lines
+
+
+Examples:
+* $SCRIPT_NAME -a an -b example           # With a description
+HELP
+
+[[ $# -lt 1 ]] && echo "$HELP" && exit 1;
+
+option_a=
+option_b="$SOME_SYSTEM_VARIABLE"
+
+while [ "${1+defined}" ]; do
+  case $1 in
+    -h|--help) echo "$HELP" && exit 0;;
+    -a|--option-a) option_a=$2; shift;;
+    -b|--option-b) option_b=$2; shift;;
+    *) echo "Unknown option $1" >&2 && exit 1;;
+  esac
+  shift
+done
diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -24,6 +24,7 @@ done
 cat <(what magic is this?)
 
 # Load an array with data
+# http://unix.stackexchange.com/questions/99423/appending-to-same-array-in-various-loops-only-last-values-remain-bash-4
 some_array=()
 while some test; do
     some_array+=("$some_variable")

diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -1,3 +1,8 @@
+# Looping per line of input
+some | command | sequence | while read var1 var2; do
+
+done
+
 # Reading a file line by line
 while read var1 var2 etc; do 
 	perform --commands --with $var1 $var2 $etc
@@ -10,4 +15,16 @@ for f in *; do
         echo "Do work";
         popd;
     fi; 
-done
+done
+
+# Test for a pattern match
+[[ $some-var =~ ^(some|regex)$ ]] && echo "Yep, it's a match!"
+
+# Process substitution: http://tldp.org/LDP/abs/html/process-sub.html
+cat <(what magic is this?)
+
+# Load an array with data
+some_array=()
+while some test; do
+    some_array+=("$some_variable")
+done < <(some command producing output)
diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -10,7 +10,4 @@ for f in *; do
         echo "Do work";
         popd;
     fi; 
-done
-
-# Alter a remote's URL
-git remote -v | cut -d' ' -f 1 | cut -f 1-2 | sed 's/something/something-else/g' | xargs -t -n 2 git remote set-url;
+done
diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -1,9 +1,9 @@
-/* Reading a file line by line */
+# Reading a file line by line
 while read var1 var2 etc; do 
 	perform --commands --with $var1 $var2 $etc
 done < some-file.ext
 
-/* The for loop with test syntax */
+# The for loop with test syntax
 for f in *; do 
     if [[ -d "$f" ]]; then
         pushd "$f";
@@ -12,5 +12,5 @@ for f in *; do
     fi; 
 done
 
-/* Alter a remote's URL */
+# Alter a remote's URL
 git remote -v | cut -d' ' -f 1 | cut -f 1-2 | sed 's/something/something-else/g' | xargs -t -n 2 git remote set-url;
diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -1,4 +1,16 @@
 /* Reading a file line by line */
 while read var1 var2 etc; do 
 	perform --commands --with $var1 $var2 $etc
-done < some-file.ext
+done < some-file.ext
+
+/* The for loop with test syntax */
+for f in *; do 
+    if [[ -d "$f" ]]; then
+        pushd "$f";
+        echo "Do work";
+        popd;
+    fi; 
+done
+
+/* Alter a remote's URL */
+git remote -v | cut -d' ' -f 1 | cut -f 1-2 | sed 's/something/something-else/g' | xargs -t -n 2 git remote set-url;
diff --git a/bash-tricks.sh b/bash-tricks.sh
@@ -0,0 +1,4 @@
+/* Reading a file line by line */
+while read var1 var2 etc; do 
+	perform --commands --with $var1 $var2 $etc
+done < some-file.ext