Defined in header <cctype> int isalpha( int ch ); Checks if the given character is an alphabetic character as classified by the currently installed C locale. In the default locale, the following characters are alphabetic: uppercase letters ABCDEFGHIJKLMNOPQRSTUVWXYZ lowercase letters abcdefghijklmnopqrstuvwxyz In locales other than "C", an alphabetic character is a character for which std::isupper() or std::islower() returns non-zero or any other character considered

Defined in header <locale> template< class charT > bool isalnum( charT ch, const locale& loc ); Checks if the given character classified as an alphanumeric character by the given locale's std::ctype facet. Parameters ch - character loc - locale Return value Returns true if the character is classified as alphanumeric, false otherwise. Possible implementation template< class charT > bool isalnum( charT ch, const std::locale& loc ) {

Defined in header <cctype> int isalnum( int ch ); Checks if the given character is an alphanumeric character as classified by the current C locale. In the default locale, the following characters are alphanumeric: digits (0123456789) uppercase letters (ABCDEFGHIJKLMNOPQRSTUVWXYZ) lowercase letters (abcdefghijklmnopqrstuvwxyz) The behavior is undefined if the value of ch is not representable as unsigned char and is not equal to EOF. Parameters ch - character

Defined in header <ios> enum class io_errc; (since C++11) The scoped enumeration std::io_errc defines the error codes reported by I/O streams in std::ios_base::failure exception objects. Only one error code (std::io_errc::stream) is required, although the implementation may define additional error codes. Because the appropriate specialization of std::is_error_code_enum is provided, values of type std::io_errc are implicitly convertible to std::error_code. Member constants

Defined in header <numeric> template< class ForwardIterator, class T > void iota( ForwardIterator first, ForwardIterator last, T value ); (since C++11) Fills the range [first, last) with sequentially increasing values, starting with value and repetitively evaluating ++value. Equivalent operation: *(d_first) = value; *(d_first+1) = ++value; *(d_first+2) = ++value; *(d_first+3) = ++value; ... Parameters first, last - the range of elements to fill with sequenti

static int xalloc(); Returns a unique (program-wide) index value that can be used to access one long and one void* elements in the private storage of std::ios_base by calling iword() and pword(). The call to xalloc does not allocate memory. This function is thread-safe; concurrent access by multiple threads does not result in a data race. (since C++14). Effectively increments a private static data member of std::ios_base, as if by executing return index++;, if index is the name of that

streamsize width() const; (1) streamsize width( streamsize new_width ); (2) Manages the minimum number of characters to generate on certain output operations and the maximum number of characters to generate on certain output operations. 1) Returns the current field width. 2) Sets the field width to the given one. Parameters new_width - new field width setting Return value The field width before the call to the function. Notes Some I/O functions call width(0) b

void unsetf( fmtflags flags ); Unsets the formatting flags identified by flags. Parameters flags - formatting flags to unset. It can be a combination of the following constants: Constant Explanation dec use decimal base for integer I/O: see std::dec oct use octal base for integer I/O: see std::oct hex use hexadecimal base for integer I/O: see std::hex basefield dec|oct|hex|0. Useful for masking operations left left adjustment (adds fill characters to the r

static bool sync_with_stdio( bool sync = true ); Sets whether the standard C++ streams are synchronized to the standard C streams after each input/output operation. The standard C++ streams are the following: std::cin, std::cout, std::cerr, std::clog, std::wcin, std::wcout, std::wcerr and std::wclog. The standard C streams are the following: stdin, stdout and stderr. For a standard stream str, synchronized with the C stream f, the following pairs of functions have identical effect: 1)

fmtflags setf( fmtflags flags ); (1) fmtflags setf( fmtflags flags, fmtflags mask ); (2) Sets the formatting flags to specified settings. 1) Sets the formatting flags identified by flags. Effectively the following operation is performed fl = fl | flags where fl defines the state of internal formatting flags. 2) Clears the formatting flags under mask, and sets the cleared flags to those specified by flags. Effectively the following operation is performed fl = (fl & ~mask) |