C

charlitos · 02-17-2009, 09:01 PM

I want to take input from the stdin into my c program but I want to terminate it when the user presses (Control - D), how can I check this from my program? How can I know the user just entered ^D?

wje_lq · 02-17-2009, 10:37 PM

Quote:

How can I know the user just entered ^D?

If you're reading from stdin, I hope you're using function fgets(); see its man page.

That man page will show you that fgets() returns NULL on end of file, and the ^D which triggered the end of file will be absorbed by the function itself; you'll never see it. Just test for that NULL.

charlitos · 02-18-2009, 12:35 AM

I was thinking of two things, one to store all the input in a single variable other one to store the input in a file. I want to do it the second way but I dont know exactly how to append line by line to this file, also I should have a way to create this new file from scratch cause I guess otherwise itll be full of garbage every time I run my script.

wje_lq · 02-18-2009, 09:46 AM

Quote:

I dont know exactly how to append line by line to this file, also I should have a way to create this new file from scratch cause I guess otherwise itll be full of garbage every time I run my script.

These two things, appending line by line to a file and recreating a file from scratch (removing any old content) are performed by library functions fopen() and fprintf().

See their man pages for further info.

charlitos · 02-18-2009, 01:02 PM

Thanks a lot guys, I had it working