Export The $PATH Variable, Line-By-Line

Bash/Coreutils, 17 16 bytes

tr : '
'<<<$PATH

Z shell (zsh), 13 bytes

<<<${(F)path}

Uses the $path parameter, which is a special array parameter used by the shell that is tied to the $PATH parameter, and a parameter expansion flag to join an array with newlines.

Batch, 41 bytes

@for %%a in ("%PATH:;=";"%")do @echo %%~a

PATH is semicolon-delimited on Windows of course. Conveniently, for splits on semicolons by default, but inconveniently, also on spaces, so I have to use string replace trickery to quote each path element before splitting. It then remains to remove the quotes afterwards.