Bash: Uppercase, Lowercase
In Bash 4, to lowercase:
var = 'Hello, World'
echo ${var,,}
hello, world
and to uppercase:
var = 'Hello, World'
echo ${var^^}
HELLO, WORLD
In Bash 4, to lowercase:
var = 'Hello, World'
echo ${var,,}
hello, world
and to uppercase:
var = 'Hello, World'
echo ${var^^}
HELLO, WORLD