DBENV->err |
#include <db.h>void DBENV->err(DB_ENV *dbenv, int error, const char *fmt, ...);
void DBENV->errx(DB_ENV *dbenv, const char *fmt, ...);
The DBENV->err, DBENV->errx, DB->err and DB->errx functions provide error-messaging functionality for applications written using the Berkeley DB library.
The DBENV->err function constructs an error message consisting of the following elements:
- An optional prefix string
- If no error callback function has been set using the DBENV->set_errcall function, any prefix string specified using the DBENV->set_errpfx function, 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 db_strerror function.
This constructed error message is then handled as follows:
If an error callback function has been set (see DB->set_errcall and DBENV->set_errcall), that function 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 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 functions perform identically to the DBENV->err and DB->err functions, except that they do not append the final separator characters and standard error string to the error message.