Programming C

The function int rand (void) returns a random number in the range from 0 to RAND_MAX.

The function void srand (unsigned int seed) provides seed for the random number generator used by the rand function.

The function int mblen (const char * str, n) returns the length of a multi-byte char pointed to by parameter str.

Function size_t mbstowcs (* pwcs, const char * str, n) Converts the sequence of multi-byte char points pointed to by the parameter str to the array pointed to by pwcs.

Int mbtowc (wchar_t * pwc, const char * str, n) converts a range of bytes into a wide char.

The function int wctomb (char * str, wchar) converts the wide char into its multi-byte representation and stores it at the beginning of the character array pointed to by str.

The file header named string.h in C Library defines a variable type, a macro and various functions to manipulate character arrays.

The function void * memchr (const void * str, int c, size_t n) looks for the first occurrence of the character c (an unsigned char) in the first n bytes of the string pointed to by

The function int memcmp (const void * str1, const void * str2, size_t n)) compares the first n bytes of two strings str1 and str2.

Function size_t wcstombs (char * str, const wchar_t * pwcs, size_t n) convert wide-char string defined by pwcs into a multibyte string starting at str. Almost all n bytes are

Function void * memcpy (void * str1, const void * str2, size_t n) copies n characters from str2 to str1.

Char * function strstr (const char * haystack, const char * needle) looks for the final occurrence of the whole needle string (not including the ending null character) that is

The function int getchar (void) in Library C takes a character (an unsigned char) from stdin. This function is equivalent to the getc function with the parameter stdin.

The function int putc (int char, FILE * stream) in Library C writes one character (an unsigned char) defined by the parameter char to the given Stream and increases the position

The function int putchar (int char) in standard C Library Writes a character (an unsigned char) defined by the char parameter to stdout.

The function int puts (const char * str) in the standard C library writes a str string to stdout (not writing null characters). A newline character (new line) is appended to the

The function int ungetc (int char, FILE * stream) in the C Library standard pushes the char character (an unsigned char) onto the Stream given to the next character to be read.

The function void perror (const char * str) in the C Library standard prints a message describing the error to stderr. First, the printed string str is followed by a colon and

The header file named stdlib.h in Standard C Library defines four variable types, a number of macros and various functions to implement common features.

The double atof function (const char * str) in Standard C Library converts a string pointed to by parameter str to a floating point number (type double).