sg_get_error(3)sg_get_error(3)NAME
sg_get_error, sg_get_error_arg, sg_get_error_errno, sg_str_error,
sg_get_error_details, sg_strperror - get last error status
SYNOPSIS
#include <statgrab.h>
sg_error sg_get_error (void);
const char *sg_get_error_arg (void);
int sg_get_error_errno (void);
sg_error sg_get_error_details (sg_error_details *err_details);
const char *sg_str_error (sg_error code);
char *sg_strperror (char **buf, const sg_error_details * const
err_details);
DESCRIPTION
There are four functions to get information about the last occurred er‐
ror: sg_get_error, sg_get_error_arg, sg_get_error_errno and sg_get_er‐
ror_details. The remaining functions are intended to improve the ma‐
chine-human-interface (e.g. the error log or a message box):
sg_str_error delivers a human readable error name and sg_strperror pre‐
pares a full blown error message for printing.
The error argument (sg_get_error_arg) is stored thread local and is
reused every time an error occures. If a later usage is intended, du‐
plicating it is a suitable strategy. Same for the error_arg of sg_er‐
ror_details delivered by sg_get_error_details.
When someone calls the function sg_get_error_details with a NULL point‐
er, the last error is overridden with a new one describing that
sg_get_error_details is called with invalid arguments. Please be care‐
ful.
The function sg_strperror is allowed to be called with or without
(err_details is NULL) collected error details. In the latter case, the
last occurred error of this thread is used to prepare the error mes‐
sage. Be aware, the the buffer pointer must be non-NULL (points to an
existing char * lvalue), but the char * lvalue it points to, must be
NULL. When invoked correctly, there are only two possible error condi‐
tions let sg_strperror fail: ENOMEM (out of memory) and EINVAL (invalid
error code).
Example
if( NULL == sg_get_cpu_stats() ) {
char *buf = NULL;
if( NULL != sg_strperror( &buf, NULL ) ) {
fprintf( stderr, "error getting CPU stats: %s\n", buf );
free(buf);
exit(255);
}
else {
fprintf( stderr, "error getting CPU stats and error information\n" );
exit(255);
}
}
RETURN VALUES
The error details contains following information:
typedef struct sg_error_details {
sg_error error;
int errno_value;
const char *error_arg;
} sg_error_details;
error The statgrab library error code.
errno_value
The operating system error code.
error_arg
Additional information set when the error was reported.
SEE ALSOstatgrab(3)WEBSITE
⟨http://www.i-scream.org/libstatgrab/⟩
i-scream 2013-06-07 sg_get_error(3)
