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-<LI><A NAME="tex2html135"
- HREF="node5.html#SECTION00051000000000000000"><SPAN CLASS="arabic">4</SPAN>.<SPAN CLASS="arabic">1</SPAN> Destroying WObj:s</A>
-<LI><A NAME="tex2html136"
- HREF="node5.html#SECTION00052000000000000000"><SPAN CLASS="arabic">4</SPAN>.<SPAN CLASS="arabic">2</SPAN> The types <TT>char*</TT> and <TT>const char*</TT> as function
- parameters and return values</A>
-</UL>
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-
-<H1><A NAME="SECTION00050000000000000000">
-<SPAN CLASS="arabic">4</SPAN> Miscellaneous design notes</A>
-</H1>
-
-<P>
-
-<H2><A NAME="SECTION00051000000000000000">
-<SPAN CLASS="arabic">4</SPAN>.<SPAN CLASS="arabic">1</SPAN> Destroying WObj:s</A>
-</H2>
-
-<P>
-To keep Ion's code as simple as possible yet safe, there are restrictions
-when the WObj
-<TT>destroy_obj</TT><A NAME="617"></A>
-function that calls watches, the deinit routine and frees memory may
-be called directly. In all other cases the <TT>mainloop_defer_destroy</TT><A NAME="618"></A>
-function should be used to defer the call of <TT>destroy_obj</TT> until
-Ioncore returns to its main event loop.
-
-<P>
-Calling the <TT>destroy_obj</TT> function directly is allowed in the
-following cases:
-
-<UL>
-<LI>In the deinit handler for another object. Usually managed objects
- are destroyed this way.
-</LI>
-<LI>The object was created during the current call to the function
- that wants to get rid of the object. This is the case, for example,
- when the function created a frame to manage some other object but for
- some reason failed to reparent the object to this frame.
-</LI>
-<LI>In a deferred action handler set with <TT>mainloop_defer_action</TT><A NAME="619"></A>.
- Like deferred destroys, other deferred actions are called when
- Ioncore has returned to the main loop.
-</LI>
-<LI>You are absolute sure that C code outside your code has no
- references to the object.
-</LI>
-</UL>
-
-<P>
-If there are no serious side effects from deferring destroying the
-object or you're unsure whether it is safe to destroy the object
-immediately, use <TT>mainloop_defer_destroy</TT>.
-
-<P>
-
-<H2><A NAME="SECTION00052000000000000000">
-<SPAN CLASS="arabic">4</SPAN>.<SPAN CLASS="arabic">2</SPAN> The types <TT>char*</TT> and <TT>const char*</TT> as function
- parameters and return values</A>
-</H2>
-
-<P>
-The following rules should apply to using strings as return values and
-parameters to functions.
-
-<P>
-<TABLE CELLPADDING=3 BORDER="1" WIDTH="100%">
-<TR><TD ALIGN="LEFT">Type</TD>
-<TD ALIGN="LEFT">Return value</TD>
-<TD ALIGN="LEFT">Parameter</TD>
-</TR>
-<TR><TD ALIGN="LEFT"><TT>const char*</TT></TD>
-<TD ALIGN="LEFT">The string is owned by the called function
- and the caller is only quaranteed short-term read access to the
- string.</TD>
-<TD ALIGN="LEFT">The called function may only read the string during its execution.
- For further reference a copy must be made.</TD>
-</TR>
-<TR><TD ALIGN="LEFT"><TT>char*</TT></TD>
-<TD ALIGN="LEFT">The string is the caller's responsibility and it
- <SPAN CLASS="textit">must</SPAN> free it when no longer needed.</TD>
-<TD ALIGN="LEFT">The called function may modify the string but the ``owner'' of
- the string is case-dependant.</TD>
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