int pmdaGetOptions(int argc , char *const * argv , pmdaOptions * opts , pmdaInterface * dispatch );
int pmdaGetOpt(int argc , char *const * argv , const char * optstring , pmdaInterface * dispatch , int * err );
The options that both pmdaGetOptions and pmdaGetOpt will trap are:
The pmdaGetOptions interface will also capture the following options, and store them within the opts parameter:
Only one of -i , -6 , -p and -u may be specified. If none of these three options is given, a pipe ( -p ) is assumed. When these options are encountered by pmdaGetOpt , the option is processed and the next option is examined. Therefore, pmdaGetOpt will only return when an option other than those listed above is found, or the end of the list is reached. The returned value will be the argument or EOF, respectively.
A PMDA can control which of these options the program will accept with either the opts or optstring argument. To accept all the options, the PMDA should call pmdaGetOptions with the short_options field of the opts structure set to the PMDA_OPTIONS macro, or pmdaGetOpt with the option string "D:d:h:i:l:pu:". Any PMDA specific options should be added to these strings in the style of getopt (3), and will be returned by both pmdaGetOptions and pmdaGetOpt if encountered.
When a command line option usage error is detected in the pmdaGetOptions interface, the error field of the opts structure will contain a non-zero error count.
pmdaGetOpt takes a pointer to an int, err , which is used as an error count. This variable should be initialized to zero before pmdaGetOpt is first called, and tested when pmdaGetOpt returns EOF.
Neither pmdaGetOptions nor pmdaGetOpt modify their argc or argv parameters.
The global variables used by the system getopt (3) interface may also be used by the caller of pmdaGetOpt within the argument parsing loop.
On the other hand, the pmdaGetOptions interface does not utilize global variables at all (neither reading nor modifying them). Instead, these variables can be access via the opts fields of the same name.