diff --git a/lib/cf-socket.c b/lib/cf-socket.c
index 9c65963ce3..74dbc65317 100644
--- a/lib/cf-socket.c
+++ b/lib/cf-socket.c
@@ -84,13 +84,13 @@
 
 
 /* retrieves ip address and port from a sockaddr structure. note it calls
- * curlx_inet_ntop which sets errno on fail, not SOCKERRNO.
+ * curlx_inet_ntop() and returns socket error.
  * @unittest 1607
  */
 UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
-                              char *addr, uint16_t *port);
+                              char *addr, uint16_t *port, int *sockerr);
 UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
-                              char *addr, uint16_t *port)
+                              char *addr, uint16_t *port, int *sockerr)
 {
   struct sockaddr_in *si = NULL;
 #ifdef USE_IPV6
@@ -105,7 +105,8 @@ UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
   switch(sa->sa_family) {
   case AF_INET:
     si = (struct sockaddr_in *)(void *)sa;
-    if(curlx_inet_ntop(sa->sa_family, &si->sin_addr, addr, MAX_IPADR_LEN)) {
+    if(curlx_inet_ntop(sa->sa_family, &si->sin_addr, addr, MAX_IPADR_LEN,
+                       sockerr)) {
       *port = ntohs(si->sin_port);
       return TRUE;
     }
@@ -113,7 +114,8 @@ UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
 #ifdef USE_IPV6
   case AF_INET6:
     si6 = (struct sockaddr_in6 *)(void *)sa;
-    if(curlx_inet_ntop(sa->sa_family, &si6->sin6_addr, addr, MAX_IPADR_LEN)) {
+    if(curlx_inet_ntop(sa->sa_family, &si6->sin6_addr, addr, MAX_IPADR_LEN,
+                       sockerr)) {
       *port = ntohs(si6->sin6_port);
       return TRUE;
     }
@@ -128,6 +130,7 @@ UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
     else
       addr[0] = 0; /* socket with no name */
     *port = 0;
+    *sockerr = 0;
     return TRUE;
 #endif
   default:
@@ -136,7 +139,7 @@ UNITTEST bool sockaddr2string(struct sockaddr *sa, curl_socklen_t salen,
 
   addr[0] = '\0';
   *port = 0;
-  errno = SOCKEAFNOSUPPORT;
+  *sockerr = SOCKEAFNOSUPPORT;
   return FALSE;
 }
 
@@ -1082,6 +1085,7 @@ static void set_local_ip(struct Curl_cfilter *cf,
 #ifdef HAVE_GETSOCKNAME
   if((ctx->sock != CURL_SOCKET_BAD) &&
      !(data->conn->scheme->protocol & CURLPROTO_TFTP)) {
+    int sockerr;
     /* TFTP does not connect, so it cannot get the IP like this */
     struct Curl_sockaddr_storage ssloc;
     curl_socklen_t slen = sizeof(struct Curl_sockaddr_storage);
@@ -1089,14 +1093,15 @@ static void set_local_ip(struct Curl_cfilter *cf,
 
     memset(&ssloc, 0, sizeof(ssloc));
     if(getsockname(ctx->sock, (struct sockaddr *)&ssloc, &slen)) {
-      VERBOSE(int sockerr = SOCKERRNO);
+      sockerr = SOCKERRNO;
       infof(data, "getsockname() failed with errno %d: %s",
             sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
     }
     else if(!sockaddr2string((struct sockaddr *)&ssloc, slen,
-                             ctx->ip.local_ip, &ctx->ip.local_port)) {
+                             ctx->ip.local_ip, &ctx->ip.local_port,
+                             &sockerr)) {
       infof(data, "ssloc inet_ntop() failed with errno %d: %s",
-            errno, curlx_strerror(errno, buffer, sizeof(buffer)));
+            sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
     }
   }
 #else
@@ -1108,21 +1113,18 @@ static CURLcode set_remote_ip(struct Curl_cfilter *cf,
                               struct Curl_easy *data)
 {
   struct cf_socket_ctx *ctx = cf->ctx;
+  int sockerr;
 
   /* store remote address and port used in this connection attempt */
   ctx->ip.transport = ctx->transport;
   if(!sockaddr2string(&ctx->addr.curl_sa_addr,
                       (curl_socklen_t)ctx->addr.addrlen,
-                      ctx->ip.remote_ip, &ctx->ip.remote_port)) {
+                      ctx->ip.remote_ip, &ctx->ip.remote_port, &sockerr)) {
     char buffer[STRERROR_LEN];
-
-    /* using bare errno instead of SOCKERRNO is safe here, because
-       sockaddr2string() calls curlx_inet_ntop(), and they both report failures
-       via errno (even on Windows builds). */
-    ctx->sockerr = errno;
+    ctx->sockerr = sockerr;
     /* malformed address or bug in inet_ntop, try next address */
     failf(data, "curl_sa_addr inet_ntop() failed with errno %d: %s",
-          errno, curlx_strerror(errno, buffer, sizeof(buffer)));
+          sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
     return CURLE_FAILED_INIT;
   }
   return CURLE_OK;
@@ -2106,6 +2108,7 @@ static void cf_tcp_set_accepted_remote_ip(struct Curl_cfilter *cf,
   struct cf_socket_ctx *ctx = cf->ctx;
 #ifdef HAVE_GETPEERNAME
   char buffer[STRERROR_LEN];
+  int sockerr;
   struct Curl_sockaddr_storage ssrem;
   curl_socklen_t plen;
 
@@ -2114,15 +2117,15 @@ static void cf_tcp_set_accepted_remote_ip(struct Curl_cfilter *cf,
   plen = sizeof(ssrem);
   memset(&ssrem, 0, plen);
   if(getpeername(ctx->sock, (struct sockaddr *)&ssrem, &plen)) {
-    int sockerr = SOCKERRNO;
+    sockerr = SOCKERRNO;
     failf(data, "getpeername() failed with errno %d: %s",
           sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
     return;
   }
   if(!sockaddr2string((struct sockaddr *)&ssrem, plen,
-                      ctx->ip.remote_ip, &ctx->ip.remote_port)) {
+                      ctx->ip.remote_ip, &ctx->ip.remote_port, &sockerr)) {
     failf(data, "ssrem inet_ntop() failed with errno %d: %s",
-          errno, curlx_strerror(errno, buffer, sizeof(buffer)));
+          sockerr, curlx_strerror(sockerr, buffer, sizeof(buffer)));
     return;
   }
 #else
diff --git a/lib/curlx/inet_ntop.c b/lib/curlx/inet_ntop.c
index 7f6028a791..751266dbbc 100644
--- a/lib/curlx/inet_ntop.c
+++ b/lib/curlx/inet_ntop.c
@@ -53,7 +53,8 @@
  *  - uses no static variables
  *  - takes an unsigned char* not an in_addr as input
  */
-static char *inet_ntop4(const unsigned char *src, char *dst, size_t size)
+static char *inet_ntop4(const unsigned char *src, char *dst, size_t size,
+                        int *sockerr)
 {
   char tmp[sizeof("255.255.255.255")];
   size_t len;
@@ -69,13 +70,12 @@ static char *inet_ntop4(const unsigned char *src, char *dst, size_t size)
 
   len = strlen(tmp);
   if(len == 0 || len >= size) {
-#ifdef USE_WINSOCK
-    errno = WSAEINVAL;
-#else
-    errno = ENOSPC;
-#endif
+    if(sockerr)
+      *sockerr = SOCKEINVAL;
     return NULL;
   }
+  if(sockerr)
+    *sockerr = 0;
   curlx_strcopy(dst, size, tmp, len);
   return dst;
 }
@@ -83,7 +83,8 @@ static char *inet_ntop4(const unsigned char *src, char *dst, size_t size)
 /*
  * Convert IPv6 binary address into presentation (printable) format.
  */
-static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
+static char *inet_ntop6(const unsigned char *src, char *dst, size_t size,
+                        int *sockerr)
 {
   /*
    * Note that int32_t and int16_t need only be "at least" large enough
@@ -152,7 +153,7 @@ static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
      */
     if(i == 6 && best.base == 0 &&
        (best.len == 6 || (best.len == 5 && words[5] == 0xffff))) {
-      if(!inet_ntop4(src + 12, tp, sizeof(tmp) - (tp - tmp))) {
+      if(!inet_ntop4(src + 12, tp, sizeof(tmp) - (tp - tmp), sockerr)) {
         return NULL;
       }
       tp += strlen(tp);
@@ -182,14 +183,12 @@ static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
 
   /* Check for overflow, copy, and we are done. */
   if((size_t)(tp - tmp) >= size) {
-#ifdef USE_WINSOCK
-    errno = WSAEINVAL;
-#else
-    errno = ENOSPC;
-#endif
+    if(sockerr)
+      *sockerr = SOCKEINVAL;
     return NULL;
   }
-
+  if(sockerr)
+    *sockerr = 0;
   curlx_strcopy(dst, size, tmp, tp - tmp);
   return dst;
 }
@@ -198,22 +197,20 @@ static char *inet_ntop6(const unsigned char *src, char *dst, size_t size)
  * Convert a network format address to presentation format.
  *
  * Returns pointer to presentation format address (`buf').
- * Returns NULL on error and errno set with the specific
- * error, EAFNOSUPPORT or ENOSPC.
- *
- * On Windows we store the error in the thread errno, not in the Winsock error
- * code. This is to avoid losing the actual last Winsock error. When this
- * function returns NULL, check errno not SOCKERRNO.
+ * Returns NULL on error and sockerr set (if not NULL) with the specific error,
+ * SOCKEAFNOSUPPORT or SOCKEINVAL.
  */
-char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size)
+char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size,
+                      int *sockerr)
 {
   switch(af) {
   case AF_INET:
-    return inet_ntop4((const unsigned char *)src, buf, size);
+    return inet_ntop4((const unsigned char *)src, buf, size, sockerr);
   case AF_INET6:
-    return inet_ntop6((const unsigned char *)src, buf, size);
+    return inet_ntop6((const unsigned char *)src, buf, size, sockerr);
   default:
-    errno = SOCKEAFNOSUPPORT;
+    if(sockerr)
+      *sockerr = SOCKEAFNOSUPPORT;
     return NULL;
   }
 }
diff --git a/lib/curlx/inet_ntop.h b/lib/curlx/inet_ntop.h
index 8f4c636d69..421a14036a 100644
--- a/lib/curlx/inet_ntop.h
+++ b/lib/curlx/inet_ntop.h
@@ -25,6 +25,7 @@
  ***************************************************************************/
 #include "curl_setup.h"
 
-char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size);
+char *curlx_inet_ntop(int af, const void *src, char *buf, size_t size,
+                      int *sockerr);
 
 #endif /* HEADER_CURL_INET_NTOP_H */
diff --git a/lib/curlx/inet_pton.c b/lib/curlx/inet_pton.c
index b3e806602a..23e76725fe 100644
--- a/lib/curlx/inet_pton.c
+++ b/lib/curlx/inet_pton.c
@@ -196,10 +196,6 @@ static int inet_pton6(const char *src, unsigned char *dst)
  *   0 if the address was not valid (`dst' is untouched in this case)
  *  -1 if some other error occurred (`dst' is untouched in this case, too)
  *
- * On Windows we store the error in the thread errno, not in the Winsock error
- * code. This is to avoid losing the actual last Winsock error. When this
- * function returns NULL, check errno not SOCKERRNO.
- *
  * author:
  *      Paul Vixie, 1996.
  */
@@ -211,7 +207,6 @@ int curlx_inet_pton(int af, const char *src, void *dst)
   case AF_INET6:
     return inet_pton6(src, (unsigned char *)dst);
   default:
-    errno = SOCKEAFNOSUPPORT;
     return -1;
   }
   /* NOTREACHED */
diff --git a/lib/ftp.c b/lib/ftp.c
index 811e58508b..3755813d00 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -1033,11 +1033,11 @@ static CURLcode ftp_port_default_host(struct Curl_easy *data,
   switch(sa->sa_family) {
 #ifdef USE_IPV6
   case AF_INET6:
-    r = curlx_inet_ntop(sa->sa_family, &sa6->sin6_addr, hbuf, hbuflen);
+    r = curlx_inet_ntop(sa->sa_family, &sa6->sin6_addr, hbuf, hbuflen, NULL);
     break;
 #endif
   default:
-    r = curlx_inet_ntop(sa->sa_family, &sa4->sin_addr, hbuf, hbuflen);
+    r = curlx_inet_ntop(sa->sa_family, &sa4->sin_addr, hbuf, hbuflen, NULL);
     break;
   }
   if(!r)
diff --git a/lib/hostip.c b/lib/hostip.c
index 7427f8fdd9..d63585f518 100644
--- a/lib/hostip.c
+++ b/lib/hostip.c
@@ -182,14 +182,16 @@ void Curl_printable_address(const struct Curl_addrinfo *ai, char *buf,
   case AF_INET: {
     const struct sockaddr_in *sa4 = (const void *)ai->ai_addr;
     const struct in_addr *ipaddr4 = &sa4->sin_addr;
-    (void)curlx_inet_ntop(ai->ai_family, (const void *)ipaddr4, buf, bufsize);
+    (void)curlx_inet_ntop(ai->ai_family, (const void *)ipaddr4, buf, bufsize,
+                          NULL);
     break;
   }
 #ifdef USE_IPV6
   case AF_INET6: {
     const struct sockaddr_in6 *sa6 = (const void *)ai->ai_addr;
     const struct in6_addr *ipaddr6 = &sa6->sin6_addr;
-    (void)curlx_inet_ntop(ai->ai_family, (const void *)ipaddr6, buf, bufsize);
+    (void)curlx_inet_ntop(ai->ai_family, (const void *)ipaddr6, buf, bufsize,
+                          NULL);
     break;
   }
 #endif
diff --git a/lib/httpsrr.c b/lib/httpsrr.c
index 441fe350b1..ac2fc2ffc9 100644
--- a/lib/httpsrr.c
+++ b/lib/httpsrr.c
@@ -82,7 +82,7 @@ static CURLcode httpsrr_print_addr(struct dynbuf *dyn,
   CURLcode result = CURLE_OK;
 
   for(i = 0; (i < (total_len / alen)) && !result; ++i) {
-    if(!curlx_inet_ntop(ai_family, addr + (i * alen), buf, sizeof(buf)))
+    if(!curlx_inet_ntop(ai_family, addr + (i * alen), buf, sizeof(buf), NULL))
       result = curlx_dyn_add(dyn, "<error parsing address>");
     else
       result = curlx_dyn_addf(dyn, "%s%s", sep, buf);
diff --git a/lib/if2ip.c b/lib/if2ip.c
index 5ae256e13c..d8b7f0142a 100644
--- a/lib/if2ip.c
+++ b/lib/if2ip.c
@@ -155,7 +155,7 @@ if2ip_result_t Curl_if2ip(int af,
               addr =
                 &((struct sockaddr_in *)(void *)iface->ifa_addr)->sin_addr;
             res = IF2IP_FOUND;
-            ip = curlx_inet_ntop(af, addr, ipstr, sizeof(ipstr));
+            ip = curlx_inet_ntop(af, addr, ipstr, sizeof(ipstr), NULL);
             curl_msnprintf(buf, buf_size, "%s%s", ip, scope);
             break;
           }
@@ -228,7 +228,7 @@ if2ip_result_t Curl_if2ip(int af,
 
   s = (struct sockaddr_in *)(void *)&req.ifr_addr;
   memcpy(&in, &s->sin_addr, sizeof(in));
-  r = curlx_inet_ntop(s->sin_family, &in, buf, buf_size);
+  r = curlx_inet_ntop(s->sin_family, &in, buf, buf_size, NULL);
 
   sclose(dummy);
   if(!r)
diff --git a/lib/urlapi.c b/lib/urlapi.c
index 1e61fbcae5..5d997b7f5d 100644
--- a/lib/urlapi.c
+++ b/lib/urlapi.c
@@ -467,7 +467,7 @@ UNITTEST CURLUcode ipv6_parse(struct Curl_URL *u, char *hostname,
     hostname[hlen] = 0; /* end the address there */
     if(curlx_inet_pton(AF_INET6, hostname, dest) != 1)
       return CURLUE_BAD_IPV6;
-    if(curlx_inet_ntop(AF_INET6, dest, hostname, hlen + 1)) {
+    if(curlx_inet_ntop(AF_INET6, dest, hostname, hlen + 1, NULL)) {
       hlen = strlen(hostname); /* might be shorter now */
       hostname[hlen + 1] = 0;
     }
diff --git a/tests/server/dnsd.c b/tests/server/dnsd.c
index 9d460d9452..73a6ebeb5c 100644
--- a/tests/server/dnsd.c
+++ b/tests/server/dnsd.c
@@ -508,7 +508,7 @@ create_resp(int qid, const struct sockaddr *addr, curl_socklen_t addrlen,
       const char *ip;
       if(add_answer(&resp->body, store, sizeof(ipv4_pref), QTYPE_A))
         goto error;
-      ip = curlx_inet_ntop(AF_INET, store, addrbuf, sizeof(addrbuf));
+      ip = curlx_inet_ntop(AF_INET, store, addrbuf, sizeof(addrbuf), NULL);
       logmsg("[%d] response A (%x) '%s'", qid, (unsigned int)QTYPE_A,
              ip ? ip : "(null)");
     }
@@ -521,7 +521,7 @@ create_resp(int qid, const struct sockaddr *addr, curl_socklen_t addrlen,
       const char *ip;
       if(add_answer(&resp->body, store, sizeof(ipv6_pref), QTYPE_AAAA))
         goto error;
-      ip = curlx_inet_ntop(AF_INET6, store, addrbuf, sizeof(addrbuf));
+      ip = curlx_inet_ntop(AF_INET6, store, addrbuf, sizeof(addrbuf), NULL);
       logmsg("[%d] response AAAA (%x) '%s'", qid, (unsigned int)QTYPE_AAAA,
              ip ? ip : "(null)");
     }
diff --git a/tests/unit/unit1607.c b/tests/unit/unit1607.c
index 2b55621340..f234588466 100644
--- a/tests/unit/unit1607.c
+++ b/tests/unit/unit1607.c
@@ -140,6 +140,7 @@ static CURLcode test_unit1607(const char *arg)
     for(j = 0; j < addressnum; ++j) {
       uint16_t port = 0;
       char ipaddress[MAX_IPADR_LEN] = { 0 };
+      int sockerr;
 
       if(!addr && !tests[i].address[j])
         break;
@@ -148,7 +149,7 @@ static CURLcode test_unit1607(const char *arg)
         continue;
 
       if(addr && !sockaddr2string(addr->ai_addr, addr->ai_addrlen,
-                                  ipaddress, &port)) {
+                                  ipaddress, &port, &sockerr)) {
         curl_mfprintf(stderr, "%s:%d tests[%zu] failed. "
                       "getaddressinfo failed.\n",
                       __FILE__, __LINE__, i);
diff --git a/tests/unit/unit1609.c b/tests/unit/unit1609.c
index d7970a5cc6..614170b946 100644
--- a/tests/unit/unit1609.c
+++ b/tests/unit/unit1609.c
@@ -142,12 +142,13 @@ static CURLcode test_unit1609(const char *arg)
     for(j = 0; j < addressnum; ++j) {
       uint16_t port = 0;
       char ipaddress[MAX_IPADR_LEN] = { 0 };
+      int sockerr;
 
       if(!addr && !tests[i].address[j])
         break;
 
       if(addr && !sockaddr2string(addr->ai_addr, addr->ai_addrlen,
-                                  ipaddress, &port)) {
+                                  ipaddress, &port, &sockerr)) {
         curl_mfprintf(stderr,
                       "%s:%d tests[%zu] failed. Curl_addr2string failed.\n",
                       __FILE__, __LINE__, i);
diff --git a/tests/unit/unit1961.c b/tests/unit/unit1961.c
index 338eeb176b..84d6e12d1f 100644
--- a/tests/unit/unit1961.c
+++ b/tests/unit/unit1961.c
@@ -57,7 +57,7 @@ static int test_ntop(void)
   ipv4a[2] = 0x64;
   ipv4a[3] = 0x01;
   ipv4a[4] = 0x01;
-  ipv4ptr = curlx_inet_ntop(AF_INET, ipv4a, ipv4res, sizeof(ipv4res));
+  ipv4ptr = curlx_inet_ntop(AF_INET, ipv4a, ipv4res, sizeof(ipv4res), NULL);
   if(!ipv4ptr)
     return 1; /* fail */
   if(ipv4ptr != ipv4res)
@@ -80,7 +80,7 @@ static int test_ntop(void)
   ipv6a[14] = 0x76;
   ipv6a[15] = 0xc8;
   ipv6a[25] = 0x01;
-  ipv6ptr = curlx_inet_ntop(AF_INET6, ipv6a, ipv6res, sizeof(ipv6res));
+  ipv6ptr = curlx_inet_ntop(AF_INET6, ipv6a, ipv6res, sizeof(ipv6res), NULL);
   if(!ipv6ptr)
     return 1; /* fail */
   if(ipv6ptr != ipv6res)
@@ -96,7 +96,7 @@ static int test_ntop(void)
   ipv6a[13] = 0x0;
   ipv6a[14] = 0x0;
   ipv6a[15] = 0x01;
-  ipv6ptr = curlx_inet_ntop(AF_INET6, ipv6a, ipv6res, sizeof(ipv6res));
+  ipv6ptr = curlx_inet_ntop(AF_INET6, ipv6a, ipv6res, sizeof(ipv6res), NULL);
   if(!ipv6ptr)
     return 1; /* fail */
   if(ipv6ptr != ipv6res)