readlink
Returns the target of a symbolic link.
Returns the filename pointed to by the symbolic link EXPR, or $_
if omitted. Returns undef on error (e.g., not a symlink, file not
found) and sets $!. Uses std::fs::read_link and converts the
result to a string via to_string_lossy.
Synopsis
my $target = readlink $symlink;
my $target = readlink '/usr/bin/perl';
my $target = readlink; # readlink($_)