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See FIO35-C. Use feof() and ferror() to detect end-of-file and file errors when sizeof(int) == sizeof(char) for the case where feof() and ferror() must be used instead.

Noncompliant Code Example (scanf())

In this noncompliant example, the call to fscanf() can result in a write outside the character array buf.

#define BUF_LENGTH 1024

void get_data(void) {
  char buf[BUF_LENGTH];
  fscanf(stdin, "%s", buf); */
  /* rest of function
}

Compliant Solution (scanf())

In this compliant solution, the call to fscanf() is constrained not to overflow buf.

#define BUF_LENGTH 1024

void get_data(void) {
  char buf[BUF_LENGTH];
  fscanf(stdin, "%1024s", buf);
  /* rest of function */
}

Noncompliant Code Example (argv)

Arguments read from the command line are stored in process memory. The function main(), called at program startup, is typically declared as follows when the program accepts command-line arguments:

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