mef@hithere.silvlis.com (Mary Ellen Foley) (11/23/89)
I have a book which says that, if you want to read in a line
at a time from standard input, you can use scanf("[^\n]\n",buffer);
Okay, you can use gets, too, and I don't know why they don't,
unless they just want to make a point about scanf. So....
#include <stdio.h>
main()
{
int result;
char buff[1024];
do
{
result = scanf("%[^\n]\n",buff);
printf("result --> %d, buff --> %s\n",result,buff);
}
while (result != EOF);
}
...seems to give the expected result on an Apollo DN4000 under
sr10.1 only if I give the EOF char (^Z) twice, if I'm running it
interactively. On the SUN (model ??) running OS 4.2 (?) (sorry, I
don't know much about SUNS),I only have to give the EOF char (^D)
once. Also, on both machines, control doesn't return from scanf
until the second line of input has gone in. That is, interactively
(on SUN) your window looks like:
foo
bar
result --> 1, buff --> foo
bas
result --> 1, buff --> bar
(^D here, but doesn't show on the screen)
result --> 1, buff --> bas
result --> -1, buff --> bas
What's going on, some sort of buffering? Where can I read about
stuff like this?
Another book tells me that scanf is slow and compiles into a
large amount of code, but didn't say why. Clearly, I need
a better set of books...
Please post answers, e-mail to my site has been flaky since our
sysadmin left (anybody out there want a sysadmin job? SUN and
Apollo and DEC equipment. Call me at 408-991-6056 for details.)
If I've overlooked something obvious, please don't flame me, just
correct me.