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.
dlfcn.h — dynamic linking
The <dlfcn.h> header shall define at least the following symbolic
constants for use in the construction of a dlopen() mode
- Relocations are performed at an implementation-defined time.
- Relocations are performed when the object is loaded.
- All symbols are available for relocation processing of other modules.
- All symbols are not made available for relocation processing by other
The following shall be declared as functions and may also be
defined as macros. Function prototypes shall be provided.
int dlclose(void *);
void *dlopen(const char *, int);
void *dlsym(void *restrict, const char *restrict);
The following sections are informative.
The System Interfaces volume of POSIX.1‐2017, dlclose(),
dlerror(), dlopen(), dlsym()
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1-2017, Standard for Information Technology -- Portable Operating
System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018
Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .
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