NS_IF_RELEASE
ns_if_release has no effect when the pointer is null.
...ns_if_release is exactly equivalent to the following function: inline void ns_if_release(nsisupports* foo) { if (foo) foo->release(); foo = 0; } syntax ns_if_release(foo); see also ns_addref, ns_release ...

Getting Started Guide
*/ ns_if_addref(afooptr); nsifoo* temp = mfooptr; mfooptr = afooptr; ns_if_release(temp); // |nscomptr|...
... */ ns_if_release(mfooptr); mfooptr = afooptr; ns_if_addref(mfooptr); // |nscomptr|...
... */ ns_if_release(mfooptr); // error: |release| is private mfooptr = afooptr; ns_if_addref(mfooptr); // error: |addref| is private second: you can't just pass the address of an nscomptr to a getter expecting to return a result through a raw xpcom interface pointer parameter.

NS_RELEASE
do not use when the pointer might be null; use ns_if_release in those cases.
... ns_release(foo) is equal to foo->release(); foo = 0; syntax ns_release(foo); see also ns_addref, ns_if_release ...

Obsolete: XPCOM-based scripting for NPAPI plugins - Archive of obsolete content
ts **)value = scriptablepeer; } else if (variable == nppvpluginscriptableiid) { nsiid* ptr = (nsiid *)npn_memalloc(sizeof(nsiid)); *ptr = scriptableiid; *(nsiid **)value = ptr; } return rv; } nperror npp_destroy (npp instance, npsaveddata** save) { if(instance == null) return nperr_invalid_instance_error; // release the scriptable object ns_if_release(instance->pdata); } original document information author(s): arun k.

An Overview of XPCOM
ns_if_release same as above but check for null before calling release.

Index
148 ns_if_addref xpcom, xpcom_macros macro 149 ns_if_release xpcom, xpcom_macros macro 150 ns_release xpcom, xpcom_macros macro 151 ns_warning xpcom, xpcom_macros macro 152 standard xpcom components components, landing, mozilla, needscontent, xpcom there are a number of components provided in the standard implementation of xpcom; these are as follows.

XPCOM reference
this macro is meant for critical errors; like assertions, ns_errors should not be reachable.ns_if_addrefmacrons_if_releasemacrons_releasemacrons_warningmacronsgetmoduleprocthis function prototype provides the xpcom entry-point into a module.nsiabcard/thunderbird3the nsiabcard interface is used to represent and manipulate cards in the address book.