1 files changed, 90 insertions, 1 deletions
diff --git a/bash.md b/bash.md
index 41e8f05..c3fe43a 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
 
@@ -26,14 +26,27 @@ Loop over integers
 
     for i in `seq 10`; do echo $i; done
 
+Loop over lines of file:
+
+    while IFS= read -r line; do
+      echo "tester: $line"
+    done < "$1"
+
 ## Conditionals
 
 * `-z`: is empty string
 * `-n`: non-empty string
 * `-f`: is regular file
+* `-d`: is a directory
 * `$A == $B`: string equality, accepts globs
 * `$A != $B`: string inequality
 
+### Numeric
+
+* `-eq`, `-ne`: equal, not equal
+* `-gt`, `-lt`: greater than, less than
+* `-ge`, `-le`: greater than or equal, less than or equal
+
 ## Heredocs
 
     cat << EOF > file
@@ -53,3 +66,79 @@ Don't interpolate variables:
     cat << 'EOF' > file
     bla bla
     EOF
+
+## Arrays
+
+Declaring indexed arrays:
+
+    declare -a name
+
+Associative arrays:
+
+    declare -A name
+
+Assignment:
+
+    # Indexed
+    array=(foo bar "baz bom"...)
+    # Associative
+    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[*]}
+    ${!array[@]}
+
+So looping:
+
+    # Over values
+    for x in "${array[@]}"; do ...
+    # Over keys (0-based indices for indexed)
+    for x in "${!array[@]}"; do ...
+
+
+Array size:
+
+    ${#array[@]}
+
+Slice:
+
+    # n elements starting at index i
+    ${array[@]:i:n}
+
+## Commandline arguments
+
+* `$#`: 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))
+
+
+## Shell optional behavior/settings/options (`shopt` builtin)
+
+    # Enable
+    shopt -s <option>
+    # Disable
+    shopt -u <option>
+
+* `nocaseglob`: glob matching is case insensitive