a couple of C questions about ASM-objc

[Paul E. Johnson]

In case you are not keeping score, I'm trying to get playmates on the
Artificial Stock Market at ArtStkMkt.sourceforge.net.

I don't want to waste Marcus's time with this, but I  figured there are
many C programmers in this list and somebody is likely to have opinions.

In the ASM version that is written in plain old objective C, I have
trouble compiling some things and I suspect the problems are platform
related.  

1. The compiler absolutely hates this in the file error.m:
FILE *msgfile = stderr;

gcc says:

  error.m:115: initializer element is not constant
  make: *** [error.o] Error 1

What do you think about that one?

2.  when I compile I get the error "getwd is not dangerious and should
not be used". In the file "util.m" it is used like this:

(this is a declaration of a global variable)
static const char *workingdir
(here's the usage)
const char *cwd(void)
{
    char pathname[MAXPATHLEN+1], *ptr;
    int len;
    extern char *getwd(char *);
    if (workingdir)
        return workingdir;
    if (getwd(pathname) == NULL)
        cerror("cwd", "Unable to get cwd: %s", pathname);
    len = strlen(pathname);
    ptr = (char *)getmem(sizeof(char)*(len+2));
    strcpy(ptr, pathname);
    ptr[len++] = PATHSEPCHAR;
    ptr[len] = EOS;
    workingdir = ptr;
    if (debug&DEBUGFILES)
        message("#f: cwd:      %s", workingdir);
    return workingdir;
}


I understand from poking around that getwd ()  is a BSD-ism that is
deprecated in GlibC-2, and that the alternative is getcwd ( x, n ),
where n is a char pointer and n is the size of space to be allocated for
the path the char pointer points to. Right?


So I would rewrite like this?

const char *cwd(void)
{
   
    if (workingdir)
        return workingdir;
     else
        getcwd( workingdir, MAXPATHLEN+1);
    if (workingdir==NULL)
         {
            printf("couldn't get wd");
            exit(1);
        }

    return workingdir;
}

But looking at this code, I can't understand why it would use "extern
char *getwd( char *); in the first place.  It declares a builtin C
library function?  And what does extern mean in an "m" file?


-- 
Paul E. Johnson                         email: address@hidden
Dept. of Political Science              http://lark.cc.ukans.edu/~pauljohn
University of Kansas                    Office: (785) 864-9086
Lawrence, Kansas 66045                  FAX: (785) 864-5700


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