[Expectperl-discuss] Suggestions for FAQ entries

[Blackstone, J. D. <jda...@ci...>]

* My spawned processs doesn't produce any output, and Expect.pm doesn't wait
for it to end.

[Might need to reword this.  Suggestions?  See
http://use.perl.org/~djberg96/journal/5430/]

Spawning a process just starts it up.  From then on, any interaction with
your process, including waiting for it to end, is up to you.  Usually this
involves expect()ing output.  If there is no output, however, you will need
to expect() a special signal sent when the process ends called eof.  Use the
array-reference syntax for expect to specify waiting for an eof:

$exp->expect($t, [qr/Possible error message/ => sub { ... }],
                 ['eof' => sub { ... }]);

(Note that unlike other expected patterns, you currently have to specify a
subroutine reference to be called when the eof is encountered.  This will
probably change in a future release.  For now, if you don't want to do
anything but wait for the program to exit, use ['eof' => sub { }], with
nothing in the curly brackets.

Expect.pm's handling of eof is based on the original TCL Expect.  More
information about original Expect's handling of eof can be found in
_Exploring Expect_ by Don Libes, p. 98.

* There's no way to reliably determine how long to set my timeouts; can't I
make it unlimited?

Yes.  Use a timeout of C<undef>, Perl's undefined value.




  After writing this, I'm not sure I liked any of the wording.  I won't be
offended if someone totally rewrites it. :)