write: The strerror() function which returns a pointer to the textual representation of the current errno value. Let’s try to simulate an error condition and try to open a file which

Value of errno: %d

errno); perror(Error printed by perror); fprintf(stderr
Error opening file: %s

strerror( errnum )); } else { fclose (pf); } return 0; } The C programming language provides perror() and strerror() functions which can be used to display the text message associated with errno.  The perror() function displays the string you pass to it
followed by a colon
a space
and then the textual representation of the current errno value.  The strerror() function
which returns a pointer to the textual representation of the current errno value. Let’s try to simulate an error condition and try to open a file which does not exist. Here I’m using both the functions to show the usage
but you can use one or more ways of printing your errors. Second important point to note is that you should use stderr file stream to output all the errors