sg_str_error (3)

\*(T<#include <statgrab.h>\*(T>

\*(T<sg_error sg_get_error\*(T> \kx \*(T<(void);\*(T>

\*(T<const char *sg_get_error_arg\*(T> \kx \*(T<(void);\*(T>

\*(T<int sg_get_error_errno\*(T> \kx \*(T<(void);\*(T>

\*(T<sg_error sg_get_error_details\*(T> \kx \*(T<(sg_error_details *err_details);\*(T>

\*(T<const char *sg_str_error\*(T> \kx \*(T<(sg_error code);\*(T>

\*(T<char *sg_strperror\*(T> \kx \*(T<(char **buf, const sg_error_details * const err_details);\*(T>

There are four functions to get information about the last occurred error: \*(T<sg_get_error\*(T>, \*(T<sg_get_error_arg\*(T>, \*(T<sg_get_error_errno\*(T> and \*(T<sg_get_error_details\*(T>. The remaining functions are intended to improve the machine-human-interface (e.g. the error log or a message box): \*(T<sg_str_error\*(T> delivers a human readable error name and \*(T<sg_strperror\*(T> prepares a full blown error message for printing.

The error argument (\*(T<sg_get_error_arg\*(T>) is stored thread local and is reused every time an error occures. If a later usage is intended, duplicating it is a suitable strategy. Same for the \*(T<error_arg\*(T> of \*(T<sg_error_details\*(T> delivered by \*(T<sg_get_error_details\*(T>.

When someone calls the function \*(T<sg_get_error_details\*(T> with a NULL pointer, the last error is overridden with a new one describing that \*(T<sg_get_error_details\*(T> is called with invalid arguments. Please be careful.

The function \*(T<sg_strperror\*(T> is allowed to be called with or without (\*(T<err_details\*(T> is NULL) collected error details. In the latter case, the last occurred error of this thread is used to prepare the error message. Be aware, the the buffer pointer must be non-NULL (points to an existing \*(T<char *\*(T> lvalue), but the \*(T<char *\*(T> lvalue it points to, must be NULL. When invoked correctly, there are only two possible error conditions let \*(T<sg_strperror\*(T> fail: ENOMEM (out of memory) and EINVAL (invalid error code).

Example

\*(T<
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);
    }
}
        \*(T>

The error details contains following information:

\*(T<
typedef struct sg_error_details {
        sg_error error;
        int errno_value;
        const char *error_arg;
} sg_error_details;
    \*(T>

\*(T<error\*(T>

The statgrab library error code.

\*(T<errno_value\*(T>

The operating system error code.

\*(T<error_arg\*(T>

Additional information set when the error was reported.

statgrab(3)

\(lahttp://www.i-scream.org/libstatgrab/\(ra