But then, if you replace the variable containing the 256 'A's with a constant string.... none of them crash, they just report '...'.

Actually, my version of the story varies a little. When assigning the command to execute as a variable, the errors have various boundaries. These boundaries differ depending on whether we use 'x' to multiply the value ($foo = 'A' x 256) or whether we assign a constant string ($foo = 'A...A'; # where length($foo) == 256). Very strange behaviour. I've gotten 3 different responses depending on length and method used. The regular "unrecognized command", the "The input line is too long" report error, and the dreaded "memory could not be written" fatal error.

I am building a list of the boundaries and results that I will post when I'm done. Sorry, this is getting too mucked up for me. Here's yet another case of the real freaky:

C:\>perl
$foo = 'A' x 255; system $foo;
$foo = 'A' x 256; system $foo;
^Z
'AAA ...<cut>... AAA' is not recognized as an internal
or external command, operable program or batch file.
Free to wrong pool 222810 not 41410065 at - line 2.

# We now get a fatal popup error with the lovely "Perl
# Command Line Interpreter has encountered a problem
# and needs to close.  We are sorry for the inconvenience."
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