Synopsis

(Required) If a function returns error information, then that error information shall be tested.

Enabled by default

Yes

Severity/Certainty

Low/Medium

Full description

Returned error information should be tested.

Coding standards

Code examples

The following code example fails the check and will give a warning:

#include<errno.h>
#include<stdio.h>

void no_test() {
  FILE * f;
  fpos_t * p;
  int x = fgetpos(f, p);
}

void test_after_overwritten() {
  FILE * f;
  fpos_t * p;
  int x = fgetpos(f, p);

  int y = fgetpos(f, p);

  switch(errno) {
  case 1:
    /* ... */
    break;
  }
}

The following code example passes the check and will not give a warning about this issue:

#include<errno.h>
#include<stdio.h>

void test() {
  FILE * f;
  fpos_t * p;
  int x = fgetpos(f, p);

  switch(errno) {
  case 1:
    /* ... */
    break;
  }
}

void test_again() {
  FILE * f;
  fpos_t * p;
  int x = fgetpos(f, p);

  switch(errno) {
  case 1:
    /* ... */
    break;
  }

  x = fgetpos(f, p);

  switch(errno) {
  case 1:
    /* ... */
    break;
  }
}