Thread: perror undefined?

I am attempting to compile some old code - it is in both C and F, and keeps falling over when I try to create .obj files in cMbedded visual C++ v 4;

warning C4013: 'perror' undefined; assuming extern returning int

Code:

#include "soilwater.h"
#include <stdlib.h>
#include <stdio.h>

    void initsite(char *sitename, SITEPAR_SPT sitepar, LAYERPAR_SPT layers,
                  FLAG_SPT flags)
    {

      int  imo, m;
      char inptline[INPTSTRLEN];
      char errmsg[INPTSTRLEN];
      FILE *fp_in;

      if (flags->debug) {
        printf("Entering function initsite\n");
      }

      if ((fp_in = fopen(sitename, "r")) == NULL) {
        sprintf(errmsg, "Cannot open file %s\n", sitename);
        perror(errmsg);
        exit(1);
      }

I don't know if there is an error in the code or if an appropriate libry is missing? any help gratefully appreciated
Amy

For compiling, I was recommended Microsoft Visual C++ version 4.0 and Microsoft Fortran PowerStation version 4.0 by the people who produced the code, so I presume that I am using the appropriate compiler, the executable will be run from command prompt, so will be able to print error there- should I be doing something with the compiler settings for that? Hopefully this answers your questions, I am very new to code, and still trying to get to grips with the terminology
Thanks

fixed by adding

void perror(const char *message);

to code- my stdio.h file is empty!

although I still don't know if it will run- any advice on where to download the real mammoth hunting compiler would be great, but yes- every link I found to it was talking about which floppy disk to do what with- even the embedded version I got requires a version of windows so old I had to dust off an old computer (which does actually have a floppy drive, although I'm not sure its wired in anymore)
anyway, I will give Microsoft Visual Studio 2010 a go if I can't get the .obj files to link, ta!