Fake error message

Python

import sys,traceback
try:
  f=open(sys.argv[0])
  print eval(f.readline())
except Exception, e:
  traceback.print_exc(0)

This is a program that should take a filename on the command line, evaluate the first line in it, and print the result. It has 2 bugs. The major bug is that it should use sys.argv[1], not sys.argv[0], so it ends up evaluating the program itself, not the contents of the file named by the first argument. The second bug is that the argument to print_exc makes it print only the deepest frame on the stack, hiding the fact that the error took place inside the eval. As a result, you get an error like this:

$ python fake_error.py twelve 
Traceback (most recent call last):
  File "<string>", line 1
     import sys,traceback
          ^
 SyntaxError: invalid syntax

This looks very much like the first line of the program has a syntax error. It's not quite right as the file is <string>, not fake_error.py, but otherwise it is indistinguishable from the case where, for example, you spell import wrong.

Both errors are somewhat "underhanded" in that they could be accidental.

Reminds me a practical joke.

$ ls -l
$ cat readme.txt
cat: readme.txt: No such file or directory
$ echo 'cat: readme.txt: No such file or directory' >readme.txt
$ ls -l
total 8
-rw-r--r--  1 florian  staff  43 Mar 16 09:52 readme.txt
$ cat readme.txt
cat: readme.txt: No such file or directory
$ 

BrainF***

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I can't find the particular compiler I used before, but I assure you that that is the exact error message.