File locations are prefixed with `$::srcdir' so that `make distcheck' can
execute the test suite using a relative path.
The current working directory is removed from the test-suite-bash-prompt.
Furthermore, no more dynamic creation of files in dir $::srcdir/fixtures since
this dir is read-only during `make distcheck'. Instead create dynamic files in
$TESTDIR/tmp
The test suite uses these "directory" variables
tcl bash description
------------ ----------- ------------------------------------
$::srcdir $SRCDIR where `fixtures' reside, relative
$::srcdirabs $SRCDIRABS where `fixtures' reside, absolute
$::TESTDIR $TESTDIR where `runtest' is invoked, absolute
