1DLERROR(P)                 POSIX Programmer's Manual                DLERROR(P)
2
3
4

NAME

6       dlerror - get diagnostic information
7

SYNOPSIS

9       #include <dlfcn.h>
10
11       char *dlerror(void);
12
13

DESCRIPTION

15       The  dlerror() function shall return a null-terminated character string
16       (with no  trailing  <newline>)  that  describes  the  last  error  that
17       occurred  during  dynamic  linking  processing.  If  no dynamic linking
18       errors have occurred since the last invocation of dlerror(),  dlerror()
19       shall return NULL.  Thus, invoking dlerror() a second time, immediately
20       following a prior invocation, shall result in NULL being returned.
21
22       The dlerror() function need not be reentrant. A function  that  is  not
23       required to be reentrant is not required to be thread-safe.
24

RETURN VALUE

26       If  successful,  dlerror()  shall  return  a  null-terminated character
27       string; otherwise, NULL shall be returned.
28

ERRORS

30       No errors are defined.
31
32       The following sections are informative.
33

EXAMPLES

35       The following example prints out the last dynamic linking error:
36
37
38              ...
39              #include <dlfcn.h>
40
41
42              char *errstr;
43
44
45              errstr = dlerror();
46              if (errstr != NULL)
47              printf ("A dynamic linking error occurred: (%s)\n", errstr);
48              ...
49

APPLICATION USAGE

51       The messages returned by dlerror() may reside in a static  buffer  that
52       is  overwritten on each call to dlerror().  Application code should not
53       write to this buffer. Programs wishing to  preserve  an  error  message
54       should make their own copies of that message. Depending on the applica‐
55       tion environment with respect to asynchronous execution events, such as
56       signals  or  other  asynchronous computation sharing the address space,
57       conforming applications should use a critical section to  retrieve  the
58       error pointer and buffer.
59

RATIONALE

61       None.
62

FUTURE DIRECTIONS

64       None.
65

SEE ALSO

67       dlclose()  ,  dlopen()  ,  dlsym()  ,  the  Base  Definitions volume of
68       IEEE Std 1003.1-2001, <dlfcn.h>
69

71       Portions of this text are reprinted and reproduced in  electronic  form
72       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
73       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
74       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
75       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
76       event of any discrepancy between this version and the original IEEE and
77       The Open Group Standard, the original IEEE and The Open Group  Standard
78       is  the  referee document. The original Standard can be obtained online
79       at http://www.opengroup.org/unix/online.html .
80
81
82
83IEEE/The Open Group                  2003                           DLERROR(P)
Impressum