If you have a structure 's' you access its members like this:

    s.onemember
    s.anothermember

When you have a pointer 'p' to a structure you access the members of the
structure like this:

    p->onemember
    p->anothermember

Or, if you like more obscure syntax:

    (*p).onemember
    (*p).anothermember

Or, for the truly strange:

    p[0].onemember
    p[0].anothermember

Bob Ammerman
RAm Systems

----- Original Message -----
From: "Lawrence Lile" <llile@toastmaster.com>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, February 26, 2002 7:30 AM
Subject: Re: [pic]:struct+pointer


> OK, what exactly does this "->" operator accomplish?  My book says it is a
> "structure pointer operator", which might as well say it was a Left Handed
> Metric 1" Macedonian Rubber-headed Fiddle Wrench and I'd still be none the
> wiser.
>
>  --Lawrence
>
> ----- Original Message -----
> From: "michael brown" <n5qmg@AMSAT.ORG>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: Tuesday, February 26, 2002 7:14 PM
> Subject: Re: [pic]:struct+pointer
>
>
> > ----- Original Message -----
> > From: "Also-Antal Csaba"
> > > But if I want change the value of temperature in the struct, with
this:
> > > (*house[index].numb).temperature=temp;
> > > I get this message:
> > > varibles.c: 108: Can't generate code for this expression (error)
> >
> > Doesn't picc allow you to say:
> >
> >  house[index]->numb->temperature=temp
> >
> > (I think this is correct, but you have a complex setup)
> >
> > > This code is work:
> > > ship1.temperature = 999;
> > >
> > > and this not:
> > >
> > > cost ship * p;
> > > p=&ship1;
> > > (*p).temperature=123;
> > > the error message is same.
> >
> > p->temperature
> >
> > >
> > > Why???
> > >
> > >
> > > typedef struct {
> > > char address;
> > >
> > > int temperature;
> > > char adjust;
> > > char max_alarm;
> > > char min_alarm;
> > > signed char tem_cal;
> > >
> > > int relhum;
> > > int pwm;
> > > char spay_time;
> > > char spay_dlay;
> > > char min_hum;
> > > char max_hum;
> > > char str_time;
> > > char stp_time;
> > > signed char rh_cal;
> > >
> > > int light;
> > > int optimum;
> > > int close_time;
> > > }ship;
> > >
> > > typedef struct {
> > > const ship * numb;
> > > }blokk;
> > >
> > >
> > >
> > > static bank3 ship ship1 = 111,210,0,400,40,-123,
> > > 550,1000,10,100,40,80,81,150,0, 134,300,4000;
> > >
> > > etc...
> > >
> > > const blokk house[] ={ & ship1,
> > > & ship2,
> > > & ship3,
> > > & ship4,
> > > & ship5,
> > > & ship6,
> > > & ship7,
> > > & ship8
> > > };
> > >
> > > --
> > > http://www.piclist.com hint: PICList Posts must start with ONE topic:
> > > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
> > >
> > >
> >
> > --
> > http://www.piclist.com hint: PICList Posts must start with ONE topic:
> > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
> >
> >
>
> --
> http://www.piclist.com hint: PICList Posts must start with ONE topic:
> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
>
>

--
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