CERT-FIO46-C_c
In this section:
Synopsis
Do not access a closed file.
Enabled by default
Yes
Severity/Certainty
Medium/Low

Full description
Using the value of a pointer to a FILE object after the associated file is closed is undefined behavior. This check is identical to RESOURCE-double-close.
Coding standards
- CERT FIO46-C
Do not access a closed file
Code examples
The following code example fails the check and will give a warning:
#include <stdio.h>
void example(void) {
FILE *f1;
f1 = fopen("test_file", "w");
fclose(f1);
fclose(f1);
}
The following code example passes the check and will not give a warning about this issue:
#include <stdio.h>
void example(void) {
FILE *f1;
f1 = fopen("test_file", "w");
fclose(f1);
}