NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c-part1/7244

Text File | 1996-08-05 | 1.3 KB | 54 lines

Path: dharma.hip.berkeley.edu!user
From: [e-mail] (gc)
Newsgroups: comp.lang.c
Subject: basic question about pointers and local vars
Date: 16 Feb 1996 18:18:18 GMT
Organization: worl domination
Message-ID: <[e-mail]>
NNTP-Posting-Host: dharma.hip.berkeley.edu
X-Newsreader: Value-Added NewsWatcher 2.0d31h+

This is basic and I should know it but I don't.  Here's my query--
So I know that if you have:

main () {
char string[10];
function(string);
...
}
function (char *string) {
   string[0] = 'a';
   string[1] = 'b';
   ....
}

This changes what the string is in main because string is a pointer.  But
what is the
standard way to get a string returned by a function if you don't want to
allocate
space for the array in main.  For example, is this valid:

main() {
char *string;
function(string);
...
}
function(char *string) {
   string = (char *)malloc(...);
   string[0] = 'a';
   string[1] = 'b';
}

It doesn't seem like it should be because the value of the pointer itself
gets changed
here and I would have thought that that gets lost when control goes back
to main, but
it does work when I try it.  So where is the problem and what is the right
way to do this?
Thanks.

--Gene Cutler
  [e-mail]
  TheRoadToNoWhere
  http://sp1.berkeley.edu/