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dlclose(3C)		 Standard C Library Functions		   dlclose(3C)

       dlclose - close a shared	object

       #include	<dlfcn.h>

       int dlclose(void	*handle);

       The  dlclose()  function	decrements the reference count of the supplied
       handle. This handle represents an executable object file	and its	depen-
       dencies,	acquired from a	previous call to dlopen(). A handle that is no
       longer referenced is processed in an attempt to unload any objects that
       are  associated	with  the handle from the current process. An unrefer-
       enced handle is no longer available to dlsym().

       Any finalization	code within an object is executed prior	to that	object
       being  unloaded.	 Any routines registered by an object using atexit(3C)
       are called prior	to that	object being unloaded. See NOTES.

       If the handle was successfully unreferenced, dlclose()  returns	0.  If
       the handle is invalid, or an error occurred as a	result of unloading an
       object, dlclose() returns a non-zero value. Additional  diagnostic  in-
       formation is available through dlerror().

       The  dlclose()  function	 is one	of a family of functions that give the
       user direct access to the dynamic linking facilities. These  facilities
       are  available to dynamically-linked processes only. See	the Linker and
       Libraries Guide.

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Interface Stability	     |Standard			   |
       |MT-Level		     |MT-Safe			   |

       ld(1),,  atexit(3C),	dladdr(3C),  dldump(3C),  dlerror(3C),
       dlopen(3C), dlsym(3C), attributes(5), standards(5)

       Linker and Libraries Guide

       A  successful  invocation of  dlclose() does not	guarantee that the ob-
       jects associated	with the handle	are removed from the address space  of
       the current process.  Objects can be referenced by multiple handles, or
       by other	objects. An object is not removed from the  address  space  of
       the current process until all references	to that	object are removed.

       Once  an	 object	has been closed	by dlclose(), referencing symbols con-
       tained in that object can cause undefined behavior.

       As part of unloading an object, finalization code within	the object  is
       called  before  the  dlclose() returns. This finalization is user code,
       and as such, can	produce	errors that can	not be	caught	by  dlclose().
       For  example,  an object	loaded using RTLD_LAZY that attempts to	call a
       function	that can not be	located, results in process termination. Erro-
       neous  programming  practices within the	finalization code can also re-
       sult in process termination. The	runtime	linkers	debugging facility can
       offer  help identifying these types of error. See the LD_DEBUG environ-
       ment variable of

SunOS 5.10			 1 March 2004			   dlclose(3C)


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