bash – La Fabulosa Vida de un IT

18/03/201104/07/2011

Associative Arrays in Bash v4

One of the new features in Bash v4 are the associative arrays using strings as index instead numbers
here a small example of use


#!/bin/bash

declare -A myArray #declare array
myArray[cat]=gato #attach a value into index cat
myArray[dog]=can #attach a value into index dog

creature="fish" #declare a variable

myArray[$creature]=peixe #attach a value into index fish

#get all array values
for key in "${!myArray[@]}"
 do
 echo "index value=$key content value= ${myArray[$key]}"
 done

22/02/201122/02/2011

Boolean and numerical values equivalence in bash

One of the problems using bash is the numeric equivalence of boolean values


#!/bin/sh
 function zero()
 {
 return 0
 }

function one()
 {
 return 1
 }

#main section
 if zero ;
 then
 echo "0 is true"
 fi
 if one ;
 then
 echo "1 is true"
 fi

and the output is:
0 is true