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Re: Params -> local vars?

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Jon Howson <nospam@nospam.com> writes:

> Hello
>
> I was reading thru some (yellowing!) mimeographed introductory notes on C 
> and I found code like the below.
>
> main(argc,argv)
>   int argc;
>   char *argv[];
> {
>   char *malloc();
>   char *strcpy();
>   int puts();
>   void free();
>
>   char *s;
>   if(argc>1 &&(s=malloc(8+strlen(argv[1])))){
>     strcpy(s,"Hello, ");
>     strcpy(s+7,argv[1]);
>     puts(s);
>     free(s);
>   }else{
>     puts("Program failed, unknown error");
>   }
> }
>
> I'm trying to work out what's happening. At the start of the function, I 
> guess the parameters are being converted into local variables, maybe a 
> way to get pass-by-value in C?

Do you mean this part?

> main(argc,argv)
>   int argc;
>   char *argv[];
> {

That's just the way parameters used to be declared.  It means exactly
the same thing as

main(int argc, char *argv[])

> Also what is the advantage of declaring the string and memory functions 
> locally to the function?

I can't think of one off-hand.

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Thread

Params -> local vars? Jon Howson <nospam@nospam.com> - 2012-07-30 19:35 +0000
  Re: Params -> local vars? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-07-30 15:54 -0400
  Re: Params -> local vars? James Kuyper <jameskuyper@verizon.net> - 2012-07-30 16:00 -0400
  Re: Params -> local vars? Kenneth Brody <kenbrody@spamcop.net> - 2012-07-30 16:01 -0400
  Re: Params -> local vars? Stephen Sprunk <stephen@sprunk.org> - 2012-07-30 15:09 -0500
    Re: Params -> local vars? Mark Bluemel <mark_bluemel@pobox.com> - 2012-07-31 08:34 +0100
      Re: Params -> local vars? Kleuske <kleuske@nowhere.net> - 2012-07-31 19:29 +0000
        Re: Params -> local vars? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-07-31 15:51 -0400
      Re: Params -> local vars? Kenneth Brody <kenbrody@spamcop.net> - 2012-08-01 15:58 -0400
  Re: Params -> local vars? Keith Thompson <kst-u@mib.org> - 2012-07-30 13:49 -0700
  Re: Params -> local vars? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2012-07-30 21:56 -0600
  Re: Params -> local vars? David T. Ashley <dashley@gmail.com> - 2012-07-31 08:42 -0400
  Re: Params -> local vars? Tim Rentsch <txr@alumni.caltech.edu> - 2012-09-07 13:39 -0700
    Re: Params -> local vars? Keith Thompson <kst-u@mib.org> - 2012-09-07 17:55 -0700
      Re: Params -> local vars? Tim Rentsch <txr@alumni.caltech.edu> - 2012-09-08 05:09 -0700
        Re: Params -> local vars? Keith Thompson <kst-u@mib.org> - 2012-09-08 11:14 -0700
        Re: Params -> local vars? Richard Damon <news.x.richarddamon@xoxy.net> - 2012-09-08 16:43 -0400
          Re: Params -> local vars? Tim Rentsch <txr@alumni.caltech.edu> - 2012-12-17 14:13 -0800

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