Test12.2: Write/Read from local output file.

Writing and reading to a file on a slow shared filesytem could cause
this test to fail.

testsuite/expect/test12.2

@@ -38,7 +38,7 @@ set file_in     "test$test_id.input"
 set file_out    "test$test_id.output"
 set file_err    "test$test_id.error"
 set file_prog   "test$test_id.prog"
-set file_name   "test$test_id.filename"
+set file_name   "/tmp/test$test_id.filename"
 set job_id      0
 set matches     0
 set aix         0