get file size

int read_filesize(char *fileName)
{
 int fileSize;
 FILE *fPtr;
 fPtr = fopen(fileName, "rb");
 if(fPtr == NULL) return -2;
 fileSize = 0;
 fseek(fPtr,0,SEEK_END);
 fileSize = ftell(fPtr);
 fclose (fPtr);
 return fileSize;
}