ioxx Namespace Reference

Asynchronous I/O for C++. More...

Classes
class	acceptor
	Accept incoming stream connections on a local network port. More...
class	core
	Asynchronous interface to socket I/O, time events, and DNS. More...
class	system_error
	Base exception class for all operating system errors. More...
class	signal_block
	Block all POSIX signals for the current scope. More...
class	system_socket
	Primary interface to system sockets. More...
Typedefs
typedef unsigned int	seconds_t
	An (unsigned) quantity of seconds.
typedef ::iovec	iovec
	The native type used for scatter/gather I/O.
typedef int	native_socket_t
	The system's native socket type.
typedef std::time_t	time_t
	The current time of day, represented in seconds since 1970-01-01 00:00:00 UTC.
typedef ::timeval	timeval
	The current time of day in microseconds since 1970-01-01 00:00:00 UTC.
Functions
template<class Result , class Predicate , class Action >
Result	throw_errno_if (Predicate is_failure, std::string const &error_msg, Action f)
	Safety-wrapper for calling POSIX system functions.
template<class Predicate , class Action >
Action::result_type	throw_errno_if (Predicate const &is_failure, std::string const &error_msg, Action const &f)
	Overloaded variant that automatically deduces the return type.
template<class Num , class Action >
Num	throw_errno_if_minus1 (std::string const &error_msg, Action const &f)
	Specialized version of throw_errno_if() for system calls that return -1 on error.
template<class Action >
Action::result_type	throw_errno_if_minus1 (std::string const &error_msg, Action const &f)
	Overloaded variant that automatically deduces the return type.
void	reset (iovec &iov, char const b, char const e)
	Set an iovec to the given byte range.
iovec	make_iovec (char const b, char const e)
	Construct ioxx::iovec using an iterator range.

Detailed Description

Asynchronous I/O for C++.

Typedef Documentation

typedef unsigned int ioxx::seconds_t

An (unsigned) quantity of seconds.

This type is useful for specifying time durations, i.e. timeouts that will occur at some point in the future.

typedef ::timeval ioxx::timeval

The current time of day in microseconds since 1970-01-01 00:00:00 UTC.

POSIX.1-2001 defines this type to contain (at least) the following members:

   struct timeval
   {
     time_t      tv_sec;     // seconds
     suseconds_t tv_usec;    // microseconds
   };

The type suseconds_t is usually signed for history reasons (it used to be a long).

Function Documentation

template<class Result , class Predicate , class Action >

Result ioxx::throw_errno_if	(	Predicate	is_failure,
		std::string const &	error_msg,
		Action	f
	)

Safety-wrapper for calling POSIX system functions.

Pretty much all system functions may fail with the EINTR condition, meaning that the call was interrupted by a signal. The throw_errno_if() combinator handles this problem transparently and restarts the function if that condition arises. All other errors will be signaled by means of a system_error exception.

Parameters:

	is_failure	Predicate of type `bool (Result)` that returns `true` if the returned value constitutes an error.
	error_msg	Context string to be used when constructing a system_error in case of an error.
	f	Functor of type `Result ()` that performs the desired system call.

Returns:: The return value returned by f.

Exceptions:

system_error Thrown if the is_failure predicate returns true.

See also:: signal_block

template<class Num , class Action >

Num ioxx::throw_errno_if_minus1	(	std::string const &	error_msg,
		Action const &	f
	)

Specialized version of throw_errno_if() for system calls that return -1 on error.

This combinator removes the need to specify an is_failure predicate.