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   error:   sg_get_error,
       sg_get_error_arg,  sg_get_error_errno  and  sg_get_error_details. The remaining functions are intended to
       improve the machine-human-interface (e.g.  the error log or a message box): sg_str_error delivers a human
       readable error name and sg_strperror prepares 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,  duplicating  it  is  a  suitable  strategy.  Same  for  the  error_arg  of
       sg_error_details delivered by sg_get_error_details.

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

       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 message.
       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 conditions
       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 ALSO

       statgrab(3)

WEBSITE

       ⟨https://libstatgrab.org/⟩