Description

The C library function, The perror() function The C library function the value of the global variable errno onto a string and writes that string to stderr. If the value of str is not null, it is written first, followed by a colon, and then the implementation-defined error message.

Declaration

Following is the declaration for perror() function.

void perror(const char *str)

Parameters

str - pointer to a null-terminated string with explanatory message.

Return Value

The perror function returns not return a value.

Example

#include <stdio.h>

int main ()
{
  FILE * p;
  p=fopen ("content.txt","rb");
  if (p==NULL)
    perror ("The following error occurred");
  else
    fclose (p);
  return 0;
}

Output

The following error occurred: No such file or directory