dlerror(3p) — Linux manual page


DLERROR(3P)               POSIX Programmer's Manual              DLERROR(3P)

PROLOG         top

       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.

NAME         top

       dlerror — get diagnostic information

SYNOPSIS         top

       #include <dlfcn.h>

       char *dlerror(void);

DESCRIPTION         top

       The dlerror() function shall return a null-terminated character
       string (with no trailing <newline>) that describes the last error
       that occurred during dynamic linking processing. If no dynamic
       linking errors have occurred since the last invocation of dlerror(),
       dlerror() shall return NULL.  Thus, invoking dlerror() a second time,
       immediately following a prior invocation, shall result in NULL being

       It is implementation-defined whether or not the dlerror() function is
       thread-safe. A thread-safe implementation shall return only errors
       that occur on the current thread.

RETURN VALUE         top

       If successful, dlerror() shall return a null-terminated character
       string; otherwise, NULL shall be returned.

       The application shall not modify the string returned. The returned
       pointer might be invalidated or the string content might be
       overwritten by a subsequent call to dlerror() in the same thread (if
       dlerror() is thread-safe) or in any thread (if dlerror() is not

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

       The following example prints out the last dynamic linking error:

           #include <dlfcn.h>

           char *errstr;

           errstr = dlerror();
           if (errstr != NULL)
               printf ("A dynamic linking error occurred: (%s)\n", errstr);


       Depending on the application environment with respect to asynchronous
       execution events, such as signals or other asynchronous computation
       sharing the address space, conforming applications should use a
       critical section to retrieve the error pointer and buffer.

RATIONALE         top




SEE ALSO         top

       dlclose(3p), dlopen(3p), dlsym(3p)

       The Base Definitions volume of POSIX.1‐2008, dlfcn.h(0p)

COPYRIGHT         top

       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 .

IEEE/The Open Group                 2013                         DLERROR(3P)

Pages that refer to this page: dlfcn.h(0p)dlclose(3p)dlopen(3p)dlsym(3p)