diff options
| author | Karl Williamson <khw@cpan.org> | 2020-03-07 12:42:23 -0700 |
|---|---|---|
| committer | Karl Williamson <khw@cpan.org> | 2020-03-16 08:16:14 -0600 |
| commit | ff2476d54be77bb2fd0a94886a9cb79e9591d506 (patch) | |
| tree | 122289dc68801a5722ce0269a88cc9e5e132b77b /ext/DynaLoader | |
| parent | 323b85475058211d2b3d4629d7e95c56bee99c53 (diff) | |
| download | perl-ff2476d54be77bb2fd0a94886a9cb79e9591d506.tar.gz | |
Dynaloader: Add, fix comments
Diffstat (limited to 'ext/DynaLoader')
| -rw-r--r-- | ext/DynaLoader/dl_dlopen.xs | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/ext/DynaLoader/dl_dlopen.xs b/ext/DynaLoader/dl_dlopen.xs index c9d164c766..9c4db0dd9b 100644 --- a/ext/DynaLoader/dl_dlopen.xs +++ b/ext/DynaLoader/dl_dlopen.xs @@ -73,6 +73,14 @@ dlerror the error message will be reset to a null pointer. The SaveError function is used to save the error as soon as it happens. + Note that the POSIX standard does not require a per-thread buffer for + the error message, and so on multi-threaded builds, it can be overwritten + by another thread before SaveError accomplishes its task. Some systems do + have a per-thread buffer. The man page on your system should tell you. + If your code might be run on a system where this function is not thread + safe, you should protect your calls with mutexes. See "Dealing with Error + Messages" below. + Return Types ============ @@ -100,7 +108,7 @@ ============================ In order to make the handling of dynamic linking errors as generic as possible you should store any error messages associated with your - implementation with the StoreError function. + implementation with the SaveError function. In the case of SunOS the function dlerror returns the error message associated with the last dynamic link error. As the SunOS dynamic @@ -113,6 +121,10 @@ Note that SaveError() takes a printf format string. Use a "%s" as the first parameter if the error may contain any % characters. + dlerror() may not be thread-safe on some systems; if this code is run on + any of those, a mutex should be added. khw (who added this comment) has no + idea which systems aren't thread-safe, but consider this possibility when + debugging. */ |