5218 posix definition of NULL
correct unistd.h and iso/stddef_iso.h
update gate source affected

@@ -17,22 +17,22 @@
    krb5_cc_cursor cur;
    krb5_creds creds;
 
    flags = 0;                           /* turns off OPENCLOSE mode */
    /* Solaris Kerberos */
-   if ((code = krb5_cc_set_flags(context, incc, flags)) != NULL)
+   if ((code = krb5_cc_set_flags(context, incc, flags)) != 0)
       return(code);
    /* Solaris Kerberos */
-   if ((code = krb5_cc_set_flags(context, outcc, flags)) != NULL)
+   if ((code = krb5_cc_set_flags(context, outcc, flags)) != 0)
       return(code);
 
    /* Solaris Kerberos */
-   if ((code = krb5_cc_start_seq_get(context, incc, &cur)) != NULL)
+   if ((code = krb5_cc_start_seq_get(context, incc, &cur)) != 0)
       goto cleanup;
 
    /* Solaris Kerberos */
-   while ((code = krb5_cc_next_cred(context, incc, &cur, &creds)) == NULL) {
+   while ((code = krb5_cc_next_cred(context, incc, &cur, &creds)) == 0) {
       if (krb5_principal_compare(context, princ, creds.server))
          continue;
 
       code = krb5_cc_store_cred(context, outcc, &creds);
       krb5_free_cred_contents(context, &creds);

@@ -163,15 +163,15 @@
       /* insert the initial cred into the ccache */
 
       if ((ret = krb5_cc_resolve(context, "MEMORY:rd_req", &ccache)))
          goto cleanup;
       /* Solaris Kerberos */
-      if ((ret = krb5_cc_initialize(context, ccache, creds->client)) != NULL)
+      if ((ret = krb5_cc_initialize(context, ccache, creds->client)) != 0)
          goto cleanup;
 
       /* Solaris Kerberos */
-      if ((ret = krb5_cc_store_cred(context, ccache, creds)) != NULL)
+      if ((ret = krb5_cc_store_cred(context, ccache, creds)) != 0)
          goto cleanup;
 
       /* set up for get_creds */
       memset(&in_creds, 0, sizeof(in_creds));
       in_creds.client = creds->client;

@@ -210,14 +210,14 @@
            krb5_ccache retcc;
 
            retcc = NULL;
 
            /* Solaris Kerberos */
-           if (((ret = krb5_cc_resolve(context, "MEMORY:rd_req2", &retcc)) != NULL) ||
-               ((ret = krb5_cc_initialize(context, retcc, creds->client)) != NULL) ||
+           if (((ret = krb5_cc_resolve(context, "MEMORY:rd_req2", &retcc)) != 0) ||
+               ((ret = krb5_cc_initialize(context, retcc, creds->client)) != 0) ||
                ((ret = krb5_cc_copy_creds_except(context, ccache, retcc,
-                                                creds->server)) != NULL)) {
+                                                creds->server)) != 0)) {
                /* Solaris Kerberos */
                if (retcc)
                    (void) krb5_cc_destroy(context, retcc);
            } else {
                *ccache_arg = retcc;