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From: lippin@ragu.berkeley.edu (The Apathist)
Newsgroups: comp.sys.mac.programmer
Subject: Re: ThinkC prototypes and Str255 args
Message-ID: <1990Sep16.003553.9541@agate.berkeley.edu>
Date: 16 Sep 90 00:35:53 GMT
References: <1990Sep15.154434.17307@midway.uchicago.edu>
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Recently fri0@quads.uchicago.edu (Christian E. Fritze) wrote:
>
>I'm using ThinkC's Class libraries with the Check Prototypes option set.
>
>I'd like to be able to call functions which expect arguments of the tye Str255
>with a string I build on the fly. If I try to pass a string to a function like
>
>SomeFunction("\pHere's my string");
>
>and the compiler expects a Str255 as an argument, I get a compile error saying
>that the argument doesn't match the prototype.

Str255 is an array of unsigned char, while string literals and
probably the string you built on the fly are arrays of signed char.  I
recommend using a cast to StringPtr for the literals, and using
Str255/StringPtr/unsigned char[] for building your own strings.  You
can avoid the cast entirely by not using string literals -- put them
in resources instead.  (Well, not entirely -- I do, but I rewrote the
prototypes for GetNamedResource and Get1NamedResource to take char *.)

The bright side to this is that pointers to pascal strings and C
strings can't be confused; you have to use an explicit cast to get the
signedness right.

					--Tom Lippincott
					  lippin@math.berkeley.edu

		"A repo man's life is always intense."
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