1 files changed, 47 insertions, 1 deletions
diff --git a/bash.md b/bash.md
index 41e8f05..8877982 100644
--- a/bash.md
+++ b/bash.md
@@ -14,7 +14,7 @@ Remove longest from start
     # e.g.
     ${FILEPATH##*/}      # get only file name portion
 
-%% - longst from end, # - shortest from start
+%% - longest from end, # - shortest from start
 
 ## Control flow
 
@@ -53,3 +53,49 @@ Don't interpolate variables:
     cat << 'EOF' > file
     bla bla
     EOF
+
+## Arrays
+
+Declaring indexed arrays:
+
+    declare -a name
+
+Associative arrays:
+
+    declare -A name
+
+Assignment:
+
+    array=([bla]=foo [ble]=bar...)
+
+All values:
+
+    ${array[*]} # one word, elements separated with first character of $IFS
+    ${array[@]} # separate words when double quoted
+
+All keys:
+
+    ${!array[*]}
+    ${!array[@]}
+
+## Commandline arguments
+
+* `$#`: number of arguments.
+
+## Getopts example
+
+    while getopts 'a:b:c' flag; do
+      case "${flag}" in
+        a) do_something $OPTARG ;;
+        b) b_option=$OPTARG ;;
+        c) c_flag=1 ;;
+        *) error "Unexpected option ${flag}" ;;
+      esac
+    done
+
+### With positional arguments
+
+Positional arguments will have to be supplied after flag options (`command
+[options] <args>`):
+
+    shift $((OPTIND-1))