KRB5_WARN(3)

NAME
krb5_abort, krb5_abortx, krb5_clear_error_string, krb5_err, krb5_errx, krb5_free_error_string, krb5_get_err_text, krb5_get_error_message, krb5_get_error_string, krb5_have_error_string, krb5_set_error_string, krb5_set_warn_dest, krb5_get_warn_dest, krb5_vabort, krb5_vabortx, krb5_verr, krb5_verrx, krb5_vset_error_string, krb5_vwarn, krb5_vwarnx, krb5_warn, krb5_warnx - Heimdal warning and error functions

LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)

SYNOPSIS
#include <krb5.h>
krb5_error_code
krb5_abort(krb5_context context, krb5_error_code code, const char *fmt, ...);
krb5_error_code
krb5_abortx(krb5_context context, krb5_error_code code, const char *fmt, ...);
void
krb5_clear_error_string(krb5_context context);
krb5_error_code
krb5_err(krb5_context context, int eval, krb5_error_code code, const char *format, ...);
krb5_error_code
krb5_errx(krb5_context context, int eval, const char *format, ...);
void
krb5_free_error_string(krb5_context context, char *str);
krb5_error_code
krb5_verr(krb5_context context, int eval, krb5_error_code code, const char *format, va_list ap);
krb5_error_code
krb5_verrx(krb5_context context, int eval, const char *format, va_list ap);
krb5_error_code
krb5_vset_error_string(krb5_context context, const char *fmt, va_list args);
krb5_error_code
krb5_vwarn(krb5_context context, krb5_error_code code, const char *format, va_list ap);
krb5_error_code
krb5_vwarnx(krb5_context context, const char *format, va_list ap);
krb5_error_code
krb5_warn(krb5_context context, krb5_error_code code, const char *format, ...);
krb5_error_code
krb5_warnx(krb5_context context, const char *format, ...);
krb5_error_code
krb5_set_error_string(krb5_context context, const char *fmt, ...);
krb5_error_code
krb5_set_warn_dest(krb5_context context, krb5_log_facility *facility);
char *
krb5_log_facility *
krb5_get_warn_dest(krb5_context context);
krb5_get_err_text(krb5_context context, krb5_error_code code);
char*
krb5_get_error_string(krb5_context context);
char*
krb5_get_error_message(krb5_context context, krb5_error_code code);
krb5_boolean
krb5_have_error_string(krb5_context context);
krb5_error_code
krb5_vabortx(krb5_context context, const char *fmt, va_list ap);
krb5_error_code
krb5_vabort(krb5_context context, const char *fmt, va_list ap);

DESCRIPTION
These functions print a warning message to some destination. format is a printf style format specifying the message to print. The forms not ending in an “x” print the error string associated with code along with the message. The “err” functions exit with exit status eval after printing the message.

Applications that want to get the error message to report it to a user or store it in a log want to use krb5_get_error_message().

The krb5_set_warn_func() function sets the destination for warning messages to the specified facility. Messages logged with the “warn” functions have a log level of 1, while the “err” functions log with level 0.

krb5_get_err_text() fetches the human readable strings describing the error-code.

krb5_abort() and krb5_abortx behaves like krb5_err and krb5_errx but instead of exiting using the exit(3) call, abort(3) is used.

krb5_free_error_string() frees the error string str returned by krb5_get_error_string().

krb5_clear_error_string() clears the error string from the context.

krb5_set_error_string() and krb5_vset_error_string() sets an verbose error string in context.

krb5_get_error_string() fetches the error string from context. The error message in the context is consumed and must be freed using krb5_free_error_string() by the caller. See also krb5_get_error_message(), what is usually less verbose to use.

krb5_have_error_string() returns TRUE if there is a verbose error message in the context.

krb5_get_error_message() fetches the error string from the context, or if there is no customized error string in context, uses code to return a error string. In either case, the error message in the context is consumed and must be freed using krb5_free_error_string() by the caller.

krb5_set_warn_dest() and krb5_get_warn_dest() sets and get the log context that is used by krb5_warn() and friends. By using this the application can control where the output should go. For example, this is imperative to inetd servers where logging status and error message will end up on the output stream to the client.

EXAMPLES
Below is a simple example how to report error messages from the Kerberos library in an application.

    #include <krb5.h>
    krb5_error_code
    function (krb5_context context)
    {
        krb5_error_code ret;
        ret = krb5_function (context, arg1, arg2);
        if (ret) {
    	char *s = krb5_get_error_message(context, ret);
    	if (s == NULL)
    	     errx(1, "kerberos error: %d (and out of memory)", ret);
    	application_logger("krb5_function failed: %s", s);
    	krb5_free_error_string(context, s);
    	return ret;
        }
        return 0;
    }

SEE ALSO
krb5(3), krb5_openlog(3)