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diff --git a/man-pages-posix-2013/man3p/dlclose.3p b/man-pages-posix-2013/man3p/dlclose.3p new file mode 100644 index 0000000..063ab5e --- /dev/null +++ b/man-pages-posix-2013/man3p/dlclose.3p @@ -0,0 +1,141 @@ +'\" et +.TH DLCLOSE "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. + +.SH NAME +dlclose +\(em close a symbol table handle +.SH SYNOPSIS +.LP +.nf +#include <dlfcn.h> +.P +int dlclose(void *\fIhandle\fP); +.fi +.SH DESCRIPTION +The +\fIdlclose\fR() +function shall inform the system that the symbol table handle specified by +.IR handle +is no longer needed by the application. +.P +An application writer may use +\fIdlclose\fR() +to make a statement of intent on the part of the process, but this +statement does not create any requirement upon the implementation. When +the symbol table handle is closed, the implementation may unload the +executable object files that were loaded by +\fIdlopen\fR() +when the symbol table handle was opened and those that were loaded by +\fIdlsym\fR() +when using the symbol table handle identified by +.IR handle . +.P +Once a symbol table handle has been closed, an application should assume +that any symbols (function identifiers and data object identifiers) +made visible using +.IR handle , +are no longer available to the process. +.P +Although a +\fIdlclose\fR() +operation is not required to remove any functions or data objects from +the address space, neither is an implementation prohibited from doing +so. The only restriction on such a removal is that no function nor data +object shall be removed to which references have been relocated, until +or unless all such references are removed. For instance, an executable +object file that had been loaded with a +\fIdlopen\fR() +operation specifying the RTLD_GLOBAL flag might provide a target for +dynamic relocations performed in the processing of other relocatable +objects\(emin such environments, an application may assume that no +relocation, once made, shall be undone or remade unless the executable +object file containing the relocated object has itself been removed. +.SH "RETURN VALUE" +If the referenced symbol table handle was successfully closed, +\fIdlclose\fR() +shall return 0. If +.IR handle +does not refer to an open symbol table handle or if the symbol table +handle could not be closed, +\fIdlclose\fR() +shall return a non-zero value. More detailed diagnostic information +shall be available through +\fIdlerror\fR(). +.SH ERRORS +No errors are defined. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +The following example illustrates use of +\fIdlopen\fR() +and +\fIdlclose\fR(): +.sp +.RS 4 +.nf +\fB +#include <dlfcn.h> +int eret; +void *mylib; +\&... +/* Open a dynamic library and then close it ... */ +mylib = dlopen("mylib.so", RTLD_LOCAL | RTLD_LAZY); +\&... +eret = dlclose(mylib); +\&... +.fi \fR +.P +.RE +.SH "APPLICATION USAGE" +A conforming application should employ a symbol table handle returned +from a +\fIdlopen\fR() +invocation only within a given scope bracketed by a +\fIdlopen\fR() +operation and the corresponding +\fIdlclose\fR() +operation. Implementations are free to use reference counting or other +techniques such that multiple calls to +\fIdlopen\fR() +referencing the same executable object file may return a pointer to the +same data object as the symbol table handle. +.P +Implementations are also free to re-use a handle. For these reasons, +the value of a handle must be treated as an opaque data type by the +application, used only in calls to +\fIdlsym\fR() +and +\fIdlclose\fR(). +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIdlerror\fR\^(\|)", +.IR "\fIdlopen\fR\^(\|)", +.IR "\fIdlsym\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "\fB<dlfcn.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.unix.org/online.html . + +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |