KeyBoardInterrupt error

[Michael Hudson]

Headers indicate evolution, so Linux, right?

Jason "Straw." <jstraw at towhee.com> writes:

> What can trigger a Keyboard Interrupt?

Receiving a SIGINT.  The terminal driver will send one of those if you
hit Ctrl-C (by default).

> I need Ctrl-C to be ignored and Ctrl-D to map to a function.

Two options for ignoring Ctrl-C: use termios to tuen off the ISIG
flag, along the lines of

import termios
import TERMIOS
n = termios.tcgetattr(0)
n[3] &=~ TERMIOS.ISIG
termios.tcsetattr(0, TERMIOS.TCSANOW, n)

but with some kind of error checking & stuff or use signal to ignore
SIGINTs:

signal.signal(signal.SIGINT,signal.SIG_IGN)

Note that when you're playing around at the console that readline
tends to reset both of these, which is nice, and that both of these
will leave ^C in the input stream (it seems).

Ctrl-D just causes reads to abort early.  If you're using raw_input()
(a) don't, if you want this level of control (b) just catch EOFErrors
and restart your loop.

> gettting a single char at a time is a bad idea for my project

Eh?  How does this relate to the above?

If you're interested in line input, you *might* want to look at my
python line reader, which was tentatively dubbed "pyrl", but needs a
new name ("pyrl" is taken).  It's not really finished; find it at:

  http://www-jcsu.jesus.cam.ac.uk/~mwh21/hacks/pyrl-0.2.0.tar.gz

To test drive, unpack & go:

$ python python_reader.py

(requires Python 2).

I've almost got incremental history searching done on my hard drive,
but a few bugs and some additional commitments have stalled me...
Anybody interested in seeing more, or have a better name than
pyttyinput?

Cheers,
M.

-- 
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