[slang-users] Does SLang_input_pending() block on receiving the abort character?

[Nate Bargmann <n0nb@xxxxxxx>]

I'm looking through the docs and played with the listing in section 6.5
of the S-Lang C Programmer's Guide.  The listing is written so that it
would appear that SLang_input_pending() passes the abort character to
SLang_getkey() so that the test of SL_UserBreak_Error would result in
the Ctl-G message being printed.  However, I am seeing the timeout
message instead as from this run:

$ ./slgetkey 

Press any key.  To quit, press Ctrl-G: g
Press any key.  To quit, press Ctrl-G: s
Press any key.  To quit, press Ctrl-G: k
Press any key.  To quit, press Ctrl-G: e
Press any key.  To quit, press Ctrl-G: Waited too long! Bye


The last line was printed immdiately upon pressing Ctl-G.

I modified the call to SLang_input_pending() to put it into an infite
while loop as follows:

        while (SLang_input_pending(5) == 0) { 
	        continue;
	}

And the output is:

$ ./slgetkey 

Press any key.  To quit, press Ctrl-G: The character is: f
Press any key.  To quit, press Ctrl-G: The character is: g
Press any key.  To quit, press Ctrl-G: The character is: h
Press any key.  To quit, press Ctrl-G: Ctrl-G pressed!  Bye
$ j

After pressing 'h' I pressed Ctl-G and the program is blocked until I
typed 'j' then it passed the test of SL_UserBreak_Error and printed the
Ctl-G message.  After exiting the 'j' character was printed to the
screen after the shell flushed the buffer.

I am running Debian Linux Unstable, Xfce Terminal, and Bash for the
shell.

- Nate

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