Global scope variables can be initialized or modified by functions. In cases where this is not desired, functions can avoid it using local variable
definitions. In subshells, the situation is different: the new context receives a copy of the global scope variables but since it's a copy, any modification
only affects the variables in the scope of the subshell, not those in the global scope. A test script can be found in
tests/variable_scope.sh.
Global variables can also be set using:
printf -v $varname %s "$value"or
IFS="" read $varname <<< "$value"Note that the read variant has problems if $2 contains multiple lines. For details, have a look at this
StackOverflow question. declare used in the context of a function
leads to localized variables.