[fpc-pascal] Using flag field in Getopts

luciano de souza luchyanus at gmail.com
Tue Oct 30 12:04:00 CET 2012

If I correctly understood, the flag field is to find arguments. If it
remains "nil", the argument was not found, otherwise, it's a pointer
to the short option.

2012/10/30, Henry Vermaak <henry.vermaak at gmail.com>:
> On 30/10/12 10:05, luciano de souza wrote:
>> Hello listers,
>> Getopts offers very good features to process commandline arguments. As
>> far as I could understand, I used it successfully. But it remains one
>> unknown aspect for me. What is the field "flag"" of TOption record?
>> How to use it?
>>   TOption = Record
>>     Name    : String;
>>     Has_arg : Integer;
>>     Flag    : PChar;
>>     Value   : Char;
>>   end;
> I think the man page for getopt explains best how this is supposed to work:
> flag specifies how results are returned for a long option.  If flag is
> NULL, then getopt_long() returns val.  (For example, the calling program
> may set val to the equivalent short option character.)  Otherwise,
> getopt_long() returns 0, and flag points to a variable which is set to
> val if the option is found, but left unchanged if the option is not found.
> Henry
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Luciano de Souza

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