examples: mention that gnutls_global_init() is optional

10 files changed, 22 insertions, 14 deletions

diff --git a/doc/examples/ex-cert-select-pkcs11.c b/doc/examples/ex-cert-select-pkcs11.c
index a7f4e7c5c3..dd16676e22 100644
--- a/doc/examples/ex-cert-select-pkcs11.c
+++ b/doc/examples/ex-cert-select-pkcs11.c
@@ -80,14 +80,15 @@ int main(void)
          */
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
-        /* PKCS11 private key operations might require PIN.
-         * Register a callback.
-         */
+
+        /* The PKCS11 private key operations may require PIN.
+         * Register a callback. */
         gnutls_pkcs11_set_pin_function(pin_callback, NULL);
 
         /* X509 stuff */
diff --git a/doc/examples/ex-cert-select.c b/doc/examples/ex-cert-select.c
index 7437e269c7..4c15f0b4e3 100644
--- a/doc/examples/ex-cert-select.c
+++ b/doc/examples/ex-cert-select.c
@@ -94,10 +94,11 @@ int main(void)
         gnutls_certificate_credentials_t xcred;
         
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         load_keys();
diff --git a/doc/examples/ex-client-dtls.c b/doc/examples/ex-client-dtls.c
index dcb0e101db..c417c0dce7 100644
--- a/doc/examples/ex-client-dtls.c
+++ b/doc/examples/ex-client-dtls.c
@@ -34,10 +34,11 @@ int main(void)
         gnutls_certificate_credentials_t xcred;
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         /* X509 stuff */
diff --git a/doc/examples/ex-client-srp.c b/doc/examples/ex-client-srp.c
index 4542724651..e02328919a 100644
--- a/doc/examples/ex-client-srp.c
+++ b/doc/examples/ex-client-srp.c
@@ -31,10 +31,11 @@ int main(void)
         gnutls_certificate_credentials_t cert_cred;
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         gnutls_srp_allocate_client_credentials(&srp_cred);
diff --git a/doc/examples/ex-client-x509.c b/doc/examples/ex-client-x509.c
index 01762e82ea..8ee429a1b2 100644
--- a/doc/examples/ex-client-x509.c
+++ b/doc/examples/ex-client-x509.c
@@ -33,10 +33,11 @@ int main(void)
         gnutls_certificate_credentials_t xcred;
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         /* X509 stuff */
diff --git a/doc/examples/ex-serv-anon.c b/doc/examples/ex-serv-anon.c
index dc0a55b90b..5c164e3531 100644
--- a/doc/examples/ex-serv-anon.c
+++ b/doc/examples/ex-serv-anon.c
@@ -55,10 +55,11 @@ int main(void)
         int optval = 1;
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         gnutls_anon_allocate_server_credentials(&anoncred);
diff --git a/doc/examples/ex-serv-pgp.c b/doc/examples/ex-serv-pgp.c
index d68a11ca49..9cd4395d75 100644
--- a/doc/examples/ex-serv-pgp.c
+++ b/doc/examples/ex-serv-pgp.c
@@ -64,10 +64,11 @@ int main(void)
         strcpy(name, "Echo Server");
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         gnutls_certificate_allocate_credentials(&cred);
diff --git a/doc/examples/ex-serv-psk.c b/doc/examples/ex-serv-psk.c
index c83658bc02..ed61f00d5e 100644
--- a/doc/examples/ex-serv-psk.c
+++ b/doc/examples/ex-serv-psk.c
@@ -79,10 +79,11 @@ int main(void)
         int kx;
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         gnutls_certificate_allocate_credentials(&x509_cred);
diff --git a/doc/examples/ex-serv-srp.c b/doc/examples/ex-serv-srp.c
index 9f1f58a2e3..c79ceb20c5 100644
--- a/doc/examples/ex-serv-srp.c
+++ b/doc/examples/ex-serv-srp.c
@@ -47,10 +47,11 @@ int main(void)
         strcpy(name, "Echo Server");
 
         if (gnutls_check_version("3.1.4") == NULL) {
-                fprintf(stderr, "GnuTLS 3.1.4 is required for this example\n");
+                fprintf(stderr, "GnuTLS 3.1.4 or later is required for this example\n");
                 exit(1);
         }
 
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         /* SRP_PASSWD a password file (created with the included srptool utility) 
diff --git a/doc/examples/ex-serv-x509.c b/doc/examples/ex-serv-x509.c
index 5380d606a4..69061e633c 100644
--- a/doc/examples/ex-serv-x509.c
+++ b/doc/examples/ex-serv-x509.c
@@ -67,8 +67,7 @@ int main(void)
         char buffer[MAX_BUF + 1];
         int optval = 1;
 
-        /* this must be called once in the program
-         */
+        /* for backwards compatibility with gnutls < 3.3.0 */
         gnutls_global_init();
 
         gnutls_certificate_allocate_credentials(&x509_cred);