#include <db.h>

void
DB->err(DB *db, int error, const char *fmt, ...);

void
DB->errx(DB *db, const char *fmt, ...);

Description: DB->err

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

The DB->err and DB_ENV->err methods constructs an error message consisting of the following elements:

An optional prefix string

If no error callback function has been set using the DB_ENV->set_errcall method, any prefix string specified using the DB_ENV->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 parameters 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 db_strerror method.

The DB->errx and DB_ENV->errx methods are the same as the DB->err and DB_ENV->err methods, except they do not append the final separator characters and standard error string to the error message.

This constructed error message is then handled as follows:

If an error callback function has been set (see DB->set_errcall and DB_ENV->set_errcall), that function is called with two parameters: any prefix string specified (see DB->set_errpfx and DB_ENV->set_errpfx) and the error message.

If a C library FILE * has been set (see DB->set_errfile and DB_ENV->set_errfile), the error message is written to that output stream.

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

Parameters

error

The error parameter is the error value for which the DB_ENV->err and DB->err methods will display a explanatory string.

fmt

The fmt parameter is an optional printf-style message to display.

Class

See Also