Defined in header <math.h> float acoshf( float arg ); (1) (since C99) double acosh( double arg ); (2) (since C99) long double acoshl( long double arg ); (3) (since C99) Defined in header <tgmath.h> #define acosh( arg ) (4) (since C99) 1-3) Computes the inverse hyperbolic cosine of arg. 4) Type-generic macro: If the argument has type long double, acoshl is called. Otherwise, if the argument has integer type or the type double, acos

Defined in header <math.h> float copysignf( float x, float y ); (1) (since C99) double copysign( double x, double y ); (2) (since C99) long double copysignl( long double x, long double y ); (3) (since C99) Defined in header <tgmath.h> #define copysign(from, to) (7) (since C99) 1-3) Composes a floating point value with the magnitude of x and the sign of y. 4) Type-generic macro: If any argument has type long double, copysignl is c

Each identifier that appears in a C program is only visible (that is, may be used) in some possibly discontiguous portion of the source code called its scope. Within a scope, an identifier may designate more than one entity only if the entities are in different name spaces. C has four kinds of scopes: block scope file scope function scope function prototype scope Nested scopes If two different entities named by the same identifier are in scope at the same time, and they belong to t

Defined in header <wchar.h> int wscanf( const wchar_t *format, ... ); (1) (since C95) int fwscanf( FILE *stream, const wchar_t *format, ... ); (2) (since C95) int swscanf( const wchar_t *buffer, const wchar_t *format, ... ); (3) (since C95) int wscanf_s( const wchar_t *restrict format, ...); (4) (since C11) int fwscanf_s( FILE *restrict stream, const wchar_t *restrict format, ...); (5) (since C11) int swscanf_s( const wchar_t *restrict

Usage while loop: as the declaration of the loop do-while loop: as the declaration of the terminating condition of the loop

Defined in header <math.h> float exp2f( float n ); (1) (since C99) double exp2( double n ); (2) (since C99) long double exp2l( long double n ); (3) (since C99) Defined in header <tgmath.h> #define exp2( n ) (4) (since C99) 1-3) Computes 2 raised to the given power n. 4) Type-generic macro: If n has type long double, exp2l is called. Otherwise, if n has integer type or the type double, exp2 is called. Otherwise, exp2f is called.

Defined in header <wctype.h> int iswpunct( wint_t ch ); (since C95) Checks if the given wide character is a punctuation character, i.e. it is one of !"#$%&'()*+,-./:;<=>?@[\]^_`{|}~ or any punctuation character specific to the current locale. Parameters ch - wide character Return value Non-zero value if the wide character is a punctuation character, zero otherwise. Example #include <stdio.h> #include <wchar.h> #include <wctype.h&g

Variadic functions are functions that may be called with different number of arguments. Only new-style (prototyped) function declarations may be variadic. This is indicated by the parameter of the form ... which must appear last in the parameter list and must follow at least one named parameter. //New-style declaration int printx(const char* fmt, ...); // function declared this way printx("hello world"); // may be called with one printx("a=%d b=%d", a, b); // or more arguments // int printy(.

Defined in header <wctype.h> int iswcntrl( wint_t ch ); (since C95) Checks if the given wide character is a control character, i.e. codes 0x00-0x1F and 0x7F and any control characters specific to the current locale. Parameters ch - wide character Return value Non-zero value if the wide character is a control character, zero otherwise. Example #include <stdio.h> #include <wchar.h> #include <wctype.h> #include <locale.h> int main(v

Defined in header <wctype.h> int iswupper( wint_t ch ); (since C95) Checks if the given wide character is an uppercase letter, i.e. one of ABCDEFGHIJKLMNOPQRSTUVWXYZ or any uppercase letter specific to the current locale. Parameters ch - wide character Return value Non-zero value if the wide character is an uppercase letter, zero otherwise. Example #include <stdio.h> #include <wchar.h> #include <wctype.h> #include <locale.h> int