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|---|---|---|
| 
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enum { NO_FILE_POS_VALUES = 3 };
int opener(FILE* file, int *width, int *height, int *data_offset) {
  int file_w;
  int file_h;
  int file_o;
  fpos_t offset;
  if (file == NULL) { return EINVAL; }
  if (fgetpos(file, &offset) != 0) { return errno; }
  if (fscanf(file, "%i %i %i", &file_w, &file_h, &file_o)  != NO_FILE_POS_VALUES) { return EIO; }
  if (fsetpos(file, &offset) != 0) { return errno; }
  if (width != NULL) { *width = file_w; }
  if (height != NULL) { *height = file_h; }
  if (data_offset != NULL) { *data_offset = file_o; }
  return 0;
}
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Compliant Solution
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| Code Block | ||
|---|---|---|
| 
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#include <errno.h>
enum { NO_FILE_POS_VALUES = 3 };
errno_t opener(FILE* file, int *width, int *height, int *data_offset) {
  int file_w;
  int file_h;
  int file_o;
  int rc;
  fpos_t offset;
  if (file == NULL) { return EINVAL; }
  if (fgetpos(file, &offset) != 0 ) { return errno; }
  if (fscanf(file, "%i %i %i", &file_w, &file_h, &file_o)  != NO_FILE_POS_VALUES) { return EIO; }
  if (fsetpos(file, &offset) != 0 ) { return errno; }
  if (width != NULL) { *width = file_w; }
  if (height != NULL) { *height = file_h; }
  if (data_offset != NULL) { *data_offset = file_o; }
  return 0;
}
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NOTE: EINVAL and EIO are not defined in C99, but they are available in most implementations and are defined in POSIX.
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