.\" Copyright (c) 2007-2017 Daniel Adler <dadler AT uni-goettingen DOT de>, 
.\"                         Tassilo Philipp <tphilipp AT potion-studios DOT com>
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.Dd $Mdocdate$
.Dt dynload 3
.Sh NAME
.Nm dynload
.Nd encapsulates dynamic loading mechanisms and
gives access to functions in foreign dynamic libraries and code modules.
.Sh SYNOPSIS
.In dynload.h
.Ft DLLib *
.Fn dlLoadLibrary "const char * libpath"
.Ft void
.Fn dlFreeLibrary "DLLib * pLib"
.Ft void *
.Fn dlFindSymbol "DLLib * pLib" "const char * pSymbolName"
.Ft DLSyms*
.Fn dlSymsInit "const char * libPath"
.Ft void
.Fn dlSymsCleanup "DLSyms * pSyms"
.Ft int
.Fn dlSymsCount "DLSyms * pSyms"
.Ft const char*
.Fn dlSymsName "DLSyms * pSyms" "int index"
.Ft const char*
.Fn dlSymsNameFromValue "DLSyms * pSyms" "void * value"
.Sh DESCRIPTION
The
.Nm
library provides an interface to load foreign dynamic libraries and access
to their symbols.
.Pp
.Fn dlLoadLibrary
loads a dynamic library at
.Ar libpath
and returns a handle to it for use in
.Fn dlFreeLibrary 
and
.Fn dlFindSymbol
calls. Passing a null pointer for the
.Ar libpath
argument is valid, and returns a handle to the main executable of the calling code. Returns a null pointer on error.
.Pp
.Fn dlFreeLibrary 
frees the loaded library with handle
.Ar pLib .
.Pp
.Fn dlFindSymbol
returns a pointer to a symbol with name
.Ar pSymbolName
in the library with handle
.Ar pLib ,
or returns a null pointer if the symbol cannot be found. The name is specified as it would appear in C source code (mangled if C++, etc.).
.Pp
The dlSyms* functions can be used to iterate over symbols. Note that they are made
for symbol name lookups, not to get a symbol's address. For that refer to
.Fn dlFindSymbol .
.Fn dlSymsInit
will return a handle (or null pointer on error) to the shared object specified by
.Ar libPath .
The returned handle is to be used with the other dlSyms* functions. The handle must be freed with
.Fn dlSymsCleanup .
.Fn dlSymsCount
returns the number of symbols in the shared object,
.Fn dlSymsName
and
.Fn dlSymsNameFromValue
are used to lookup symbol names using an index or symbol's address, respectively, returning a null pointer on error. The names are returned as they would appear in C source code (mangled if C++, etc.). The address passed to
.Fn dlSymsNameFromValue
must point to a loaded symbol.
.Sh SEE ALSO
.Xr dyncall 3 ,
.Xr dyncallback 3
and the dyncall manual (available in HTML and PDF format) for more information.
.Sh AUTHORS
.An "Daniel Adler" Aq dadler@uni-goettingen.de
.An "Tassilo Philipp" Aq tphilipp@potion-studios.com