For every c program it is required to have a proper error handling mechanism that can deal with errors which occur at runtime. Error handling is the process of responding to the occurrence of any error that occurs during the computation, of exceptions.
errno, perror() and strerror() :
In C Programming Language we have perror() and strerror() functions which can be used to display the text message associated with errno.
perror() : It displays the string you pass to it, followed by a colon, a space, and then the textual representation of the current errno value.
strerror() : It returns a pointer to the textual representation of the current errno value.
stderr : It is file stream to output the errors.