Exercise 1-22 in the K&R. What error is responsible?

rtmistler · 09-12-2020, 04:59 PM

You can either modify to read from an array so you don't need to use stdin, or use the terminal capabilities https://sourceware.org/gdb/current/o...02fOutput.html

GazL · 09-13-2020, 02:54 AM

Quote:

Originally Posted by Arct1c_f0x

So the problem that I'm running into now is using GDB (with emacs or even just by itself) and not being able to accept user input from stdin. I'll keep searching stack exchange and other sites for how to do this but if you know how to accomplish this (and I strongly suspect that you do), it would be a welcomed advancement.

When you use gdb through emacs you'll get an input/output buffer that you can use for providing stdin and reading stdout. It's a little clunky but it works. Best bet is to split your emacs screen into 3 so you can see, source, in/out and the gdb control window all at the same time.

The other option is to connect it to external ttys: which was described in the link rtmistler provided above, but unless you're doing some terminal programming (using escape sequences, or ncurses) that'll likely be more trouble than its worth.

rtmistler · 09-13-2020, 12:54 PM

This all started with a segmentation fault. That should be easy to track down by inspecting the core file in the debugger. Backtrace on the core file.

I agree that normal validation is faster using print statements.

Also agree that designing a solution in advance of coding is the right thing to do. Too many people get too distracted by simple code tasks as opposed to the problem and solution.

pan64 · 09-14-2020, 01:55 AM

about debuggers: you may try ddd, a graphical frontend to gdb, probably easier (this works without emacs).

Arct1c_f0x · 09-14-2020, 07:49 AM

Quote:

Originally Posted by GazL

When you use gdb through emacs you'll get an input/output buffer that you can use for providing stdin and reading stdout. It's a little clunky but it works. Best bet is to split your emacs screen into 3 so you can see, source, in/out and the gdb control window all at the same time.

The other option is to connect it to external ttys: which was described in the link rtmistler provided above, but unless you're doing some terminal programming (using escape sequences, or ncurses) that'll likely be more trouble than its worth.

Thanks! I'm going to try that.