#include <db_cxx.h>

Db::err(int error, const char *fmt, ...);

Db::errx(const char *fmt, ...);

Description

The DbEnv::err, DbEnv::errx, Db::err and Db::errx methods provide error-messaging functionality for applications written using the Berkeley DB library.

The DbEnv::err method constructs an error message consisting of the following elements:

An optional prefix string

If no error callback method has been set using the DbEnv::set_errcall method, any prefix string specified using the DbEnv::set_errpfx method, followed by two separating characters: a colon and a <space> character.

An optional printf-style message

The supplied message fmt, if non-NULL, in which the ANSI C X3.159-1989 (ANSI C) printf function specifies how subsequent arguments are converted for output.

A separator

Two separating characters: a colon and a <space> character.

A standard error string

The standard system or Berkeley DB library error string associated with the error value, as returned by the DbEnv::strerror method.

This constructed error message is then handled as follows:

If an error callback method has been set (see Db::set_errcall and DbEnv::set_errcall), that method is called with two arguments: any prefix string specified (see Db::set_errpfx and DbEnv::set_errpfx) and the error message.

If a C library FILE * has been set (see Db::set_errfile and DbEnv::set_errfile), the error message is written to that output stream.

If a C++ ostream has been set (see DbEnv::set_error_stream and Db::set_error_stream), the error message is written to that stream.

If none of these output options has been configured, the error message is written to stderr, the standard error output stream.

The DbEnv::errx and Db::errx methods perform identically to the DbEnv::err and Db::err methods, except that they do not append the final separator characters and standard error string to the error message.

Class

See Also