The strchr () function in C
char * strchr function (const char * str, int c) looks for the first occurrence of the character c (an unsigned char) in the string pointed to by parameter str.
Tags : running commands in c
The strerror () function in C
the function char * strerror (int errnum) searches for an internal array for errnum error numbers and returns a pointer to a string of error messages.
The strlen () function in C
the function size_t strlen (const char * str) calculates the length of str string (not including the ending null character).