#!/bin/bash # Pitfalls of variables in a subshell. outer_variable=outer echo echo "outer_variable = $outer_variable" echo ( # Begin subshell echo "outer_variable inside subshell = $outer_variable" inner_variable=inner # Set echo "inner_variable inside subshell = $inner_variable" outer_variable=inner # Will value change globally? echo "outer_variable inside subshell = $outer_variable" # Will 'exporting' make a difference? # export inner_variable # export outer_variable # Try it and see. # End subshell ) echo echo "inner_variable outside subshell = $inner_variable" # Unset. echo "outer_variable outside subshell = $outer_variable" # Unchanged. echo exit 0 # What happens if you uncomment lines 19 and 20? # Does it make a difference?