Use the return value from write(2)

This prevents a warning when building with crypto-mdebug.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3836)

1 files changed, 5 insertions, 2 deletions

diff --git a/crypto/mem.c b/crypto/mem.c
index aa5ac56b47..81a73ccdde 100644
--- a/crypto/mem.c
+++ b/crypto/mem.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -126,13 +126,16 @@ static int shouldfail(void)
 {
     int roll = (int)(random() % 100);
     int shoulditfail = roll < md_fail_percent;
+    int len;
     char buff[80];
 
     if (md_tracefd > 0) {
         BIO_snprintf(buff, sizeof(buff),
                      "%c C%ld %%%d R%d\n",
                      shoulditfail ? '-' : '+', md_count, md_fail_percent, roll);
-        write(md_tracefd, buff, strlen(buff));
+        len = strlen(buff);
+        if (write(md_tracefd, buff, len) != len)
+            perror("shouldfail write failed");
 #ifndef OPENSSL_NO_CRYPTO_MDEBUG_BACKTRACE
         if (shoulditfail) {
             void *addrs[30];