include/openssl: don't include <windows.h> in public headers.

[openssl.git] / doc / crypto / CRYPTO_THREAD_run_once.pod

diff --git a/doc/crypto/CRYPTO_THREAD_run_once.pod b/doc/crypto/CRYPTO_THREAD_run_once.pod
index 37671b90ebe50e745af8443f6f10ea051cebe058..7795a04477016ce1bd99aac34e7f8a10c5553983 100644 (file)
--- a/doc/crypto/CRYPTO_THREAD_run_once.pod
+++ b/doc/crypto/CRYPTO_THREAD_run_once.pod
@@ -79,10 +79,23 @@ CRYPTO_THREAD_lock_frees() returns no value.
 
 The other functions return 1 on success or 0 on error.
 
+=head1 NOTES
+
+On Windows platforms the CRYPTO_THREAD_* types and functions in the
+openssl/crypto.h header are dependent on some of the types customarily
+made available by including windows.h. The application developer is
+likely to require control over when the latter is included, commonly as
+one of the first included headers. Therefore it is defined as an
+application developer's responsibility to include windows.h prior to
+crypto.h where use of CRYPTO_THREAD_* types and functions is required.
+
 =head1 EXAMPLE
 
 This example safely initializes and uses a lock.
 
+  #ifdef _WIN32
+  # include <windows.h>
+  #endif
   #include <openssl/crypto.h>
 
   static CRYPTO_ONCE once = CRYPTO_ONCE_STATIC_INIT;