Copyright (C) 1994, Digital Equipment Corp.
UNSAFE INTERFACE M3toC;
IMPORT Ctypes;
PROCEDURE CopyTtoS(t: TEXT): Ctypes.char_star;
Return a null-terminated C string with the same contents as t
,
but not sharing any storage with t
. The result should be passed
to FreeCopiedS
after it is irrelevant.
PROCEDURE FreeCopiedS(s: Ctypes.char_star);
Free the storage for s
, which must have been returned from a call
of CopyTtoS
. It is an unchecked runtime error to free s
more
than once or to use s
after calling FreeCopiedS(s)
.
PROCEDURE TtoS(t: TEXT): Ctypes.char_star;
Return a null-terminated C string with the same contents as t
,
and sharing storage with t
. FreeCopiedS
should {\em not}
be called on the value returned by TtoS
.
It is the client's responsibility to prevent the garbage collector
from collecting or moving t
while the result of TtoS(t)
is
being used. One way to accomplish this is to maintain a reference
to (or into) t
on the stack or in the registers of any thread.
Alternatively, the collector can be disabled. See the
RTCollector
interface for details.
PROCEDURE StoT(s: Ctypes.char_star): TEXT;
Return a text with the same contents as the null-terminated C
string s
and sharing storage with t
. The result is invalid
after s
is freed.
PROCEDURE CopyStoT(s: Ctypes.char_star): TEXT;
Return a text with the same contents as the null-terminated C
string s
. This copies s
, so the result is valid even if s
is
later freed.
END M3toC.