V2600. MISRA. The standard input/output functions should not be used.

This diagnostic rule is based on the MISRA (Motor Industry Software Reliability Association) manual for software development.

The standard library functions from the '<stdio.h>' / '<cstdio>' and '<wchar.h>' header files can be dangerous. Their behavior depends on the implementation. Besides, their use may lead to undefined behavior.

Look at the code fragment:

#include <stdio.h>

void InputFromFile(FILE *file); // Read from 'file'

void foo()
{
  FILE *stream;
  ....
  InputFromFile(stream);
  fflush(stream);
}

First, the code reads data via the 'stream' file descriptor, which is then passed to the 'fflush' function. This sequence of operations leads to undefined behavior.

The analyzer issues a warning if it detects the use of any functions defined in the '<stdio.h>' / '<cstdio>' and '<wchar.h>' header files:

• fopen;
• fclose;
• freopen;
• fflush;
• setbuf;
• setvbuf;
• etc.

For example, the analyzer issues a warning for the code below:

#include <stdio.h>

void foo(const char *filename, FILE *oldFd)
{
  FILE *newFd = freopen(filename, "r", oldFd);
  ....
}

This diagnostic is classified as: