diff --git a/lib/cf-socket.c b/lib/cf-socket.c
index e30f605adb..fb9160a391 100644
--- a/lib/cf-socket.c
+++ b/lib/cf-socket.c
@@ -939,32 +939,19 @@ static bool verifyconnect(curl_socket_t sockfd, int *error)
 static CURLcode socket_connect_result(struct Curl_easy *data,
                                       const char *ipaddress, int error)
 {
-  switch(error) {
-  case SOCKEINPROGRESS:
-  case SOCKEWOULDBLOCK:
-#ifdef EAGAIN
-#if (EAGAIN) != (SOCKEWOULDBLOCK)
-    /* On some platforms EAGAIN and EWOULDBLOCK are the
-     * same value, and on others they are different, hence
-     * the odd #if
-     */
-  case EAGAIN:
-#endif
-#endif
+  if(error == SOCKEINPROGRESS || SOCK_EAGAIN(error))
     return CURLE_OK;
 
-  default:
-    /* unknown error, fallthrough and try another address! */
-    {
-      VERBOSE(char buffer[STRERROR_LEN]);
-      infof(data, "Immediate connect fail for %s: %s", ipaddress,
-            curlx_strerror(error, buffer, sizeof(buffer)));
-      NOVERBOSE((void)ipaddress);
-    }
-    data->state.os_errno = error;
-    /* connect failed */
-    return CURLE_COULDNT_CONNECT;
+  /* unknown error, fallthrough and try another address! */
+  {
+    VERBOSE(char buffer[STRERROR_LEN]);
+    infof(data, "Immediate connect fail for %s: %s", ipaddress,
+          curlx_strerror(error, buffer, sizeof(buffer)));
+    NOVERBOSE((void)ipaddress);
   }
+  data->state.os_errno = error;
+  /* connect failed */
+  return CURLE_COULDNT_CONNECT;
 }
 
 struct cf_socket_ctx {
@@ -1560,22 +1547,12 @@ static CURLcode cf_socket_send(struct Curl_cfilter *cf, struct Curl_easy *data,
 
   if(!curlx_sztouz(rv, pnwritten)) {
     int sockerr = SOCKERRNO;
-
-    if(
-#ifdef USE_WINSOCK
-      /* This is how Windows does it */
-      (SOCKEWOULDBLOCK == sockerr)
-#else
-      /* errno may be EWOULDBLOCK or on some systems EAGAIN when it returned
-         due to its inability to send off data without blocking. We therefore
-         treat both error codes the same here */
-      (SOCKEWOULDBLOCK == sockerr) ||
-      (EAGAIN == sockerr) || (SOCKEINTR == sockerr) ||
-      (SOCKEINPROGRESS == sockerr)
+    if(SOCK_EAGAIN(sockerr)
+#ifndef USE_WINSOCK
+       || (sockerr == SOCKEINTR) || (sockerr == SOCKEINPROGRESS)
 #endif
       ) {
-      /* EWOULDBLOCK */
-      result = CURLE_AGAIN;
+      result = CURLE_AGAIN;  /* EWOULDBLOCK */
     }
     else {
       char buffer[STRERROR_LEN];
@@ -1626,21 +1603,12 @@ static CURLcode cf_socket_recv(struct Curl_cfilter *cf, struct Curl_easy *data,
 
   if(!curlx_sztouz(rv, pnread)) {
     int sockerr = SOCKERRNO;
-
-    if(
-#ifdef USE_WINSOCK
-      /* This is how Windows does it */
-      (SOCKEWOULDBLOCK == sockerr)
-#else
-      /* errno may be EWOULDBLOCK or on some systems EAGAIN when it returned
-         due to its inability to send off data without blocking. We therefore
-         treat both error codes the same here */
-      (SOCKEWOULDBLOCK == sockerr) ||
-      (EAGAIN == sockerr) || (SOCKEINTR == sockerr)
+    if(SOCK_EAGAIN(sockerr)
+#ifndef USE_WINSOCK
+       || (sockerr == SOCKEINTR)
 #endif
       ) {
-      /* EWOULDBLOCK */
-      result = CURLE_AGAIN;
+      result = CURLE_AGAIN;  /* EWOULDBLOCK */
     }
     else {
       char buffer[STRERROR_LEN];
diff --git a/lib/curl_setup.h b/lib/curl_setup.h
index 3878503271..0bbf717c89 100644
--- a/lib/curl_setup.h
+++ b/lib/curl_setup.h
@@ -1137,6 +1137,15 @@ typedef unsigned int curl_bit;
 #define SOCKEWOULDBLOCK   EWOULDBLOCK
 #endif
 
+/* The socket error may be EWOULDBLOCK or on some systems EAGAIN when
+   it returned due to its inability to send/read data without blocking.
+   We treat both error codes the same here. */
+#if !defined(USE_WINSOCK) && EAGAIN != SOCKEWOULDBLOCK
+#define SOCK_EAGAIN(e) ((e) == SOCKEWOULDBLOCK || (e) == EAGAIN)
+#else
+#define SOCK_EAGAIN(e) ((e) == SOCKEWOULDBLOCK)
+#endif
+
 /*
  * Macro argv_item_t hides platform details to code using it.
  */
diff --git a/lib/socketpair.c b/lib/socketpair.c
index 76b959dd4a..ed410ec180 100644
--- a/lib/socketpair.c
+++ b/lib/socketpair.c
@@ -232,16 +232,9 @@ static int wakeup_inet(curl_socket_t socks[2], bool nonblocking)
         /* Do not block forever */
         if(curlx_timediff_ms(curlx_now(), start) > (60 * 1000))
           goto error;
-        if(
-#ifdef USE_WINSOCK
-           /* This is how Windows does it */
-           (SOCKEWOULDBLOCK == sockerr)
-#else
-           /* errno may be EWOULDBLOCK or on some systems EAGAIN when it
-              returned due to its inability to send off data without
-              blocking. We therefore treat both error codes the same here */
-           (SOCKEWOULDBLOCK == sockerr) || (EAGAIN == sockerr) ||
-           (SOCKEINTR == sockerr) || (SOCKEINPROGRESS == sockerr)
+        if(SOCK_EAGAIN(sockerr)
+#ifndef USE_WINSOCK
+           || (sockerr == SOCKEINTR) || (sockerr == SOCKEINPROGRESS)
 #endif
           ) {
           continue;
@@ -320,15 +313,12 @@ int Curl_wakeup_signal(curl_socket_t socks[2])
     err = 0;
     if(wakeup_write(socks[1], buf, sizeof(buf)) < 0) {
       err = SOCKERRNO;
-#ifdef USE_WINSOCK
-      if(err == SOCKEWOULDBLOCK)
-        err = 0; /* wakeup is already ongoing */
-#else
-      if(SOCKEINTR == err)
+#ifndef USE_WINSOCK
+      if(err == SOCKEINTR)
         continue;
-      if((err == SOCKEWOULDBLOCK) || (err == EAGAIN))
-        err = 0; /* wakeup is already ongoing */
 #endif
+      if(SOCK_EAGAIN(err))
+        err = 0; /* wakeup is already ongoing */
     }
     break;
   }
@@ -346,15 +336,13 @@ CURLcode Curl_wakeup_consume(curl_socket_t socks[2], bool all)
     if(!rc)
       break;
     else if(rc < 0) {
-#ifdef USE_WINSOCK
-      if(SOCKERRNO == SOCKEWOULDBLOCK)
-        break;
-#else
-      if(SOCKEINTR == SOCKERRNO)
+      int sockerr = SOCKERRNO;
+#ifndef USE_WINSOCK
+      if(sockerr == SOCKEINTR)
         continue;
-      if((SOCKERRNO == SOCKEWOULDBLOCK) || (SOCKERRNO == EAGAIN))
-        break;
 #endif
+      if(SOCK_EAGAIN(sockerr))
+        break;
       result = CURLE_READ_ERROR;
       break;
     }
diff --git a/lib/vquic/vquic.c b/lib/vquic/vquic.c
index d187a7d17e..fe5683dbd3 100644
--- a/lib/vquic/vquic.c
+++ b/lib/vquic/vquic.c
@@ -165,12 +165,10 @@ static CURLcode do_sendmsg(struct Curl_cfilter *cf,
     ;
 
   if(!curlx_sztouz(rv, psent)) {
-    switch(SOCKERRNO) {
-    case EAGAIN:
-#if EAGAIN != SOCKEWOULDBLOCK
-    case SOCKEWOULDBLOCK:
-#endif
+    int sockerr = SOCKERRNO;
+    if(SOCK_EAGAIN(sockerr))
       return CURLE_AGAIN;
+    switch(sockerr) {
     case SOCKEMSGSIZE:
       /* UDP datagram is too large; caused by PMTUD. Let it be lost. */
       *psent = pktlen;
@@ -179,13 +177,13 @@ static CURLcode do_sendmsg(struct Curl_cfilter *cf,
       if(pktlen > gsolen) {
         /* GSO failure */
         infof(data, "sendmsg() returned %zd (errno %d); disable GSO", rv,
-              SOCKERRNO);
+              sockerr);
         qctx->no_gso = TRUE;
         return send_packet_no_gso(cf, data, qctx, pkt, pktlen, gsolen, psent);
       }
       FALLTHROUGH();
     default:
-      failf(data, "sendmsg() returned %zd (errno %d)", rv, SOCKERRNO);
+      failf(data, "sendmsg() returned %zd (errno %d)", rv, sockerr);
       result = CURLE_SEND_ERROR;
       goto out;
     }
@@ -206,7 +204,7 @@ static CURLcode do_sendmsg(struct Curl_cfilter *cf,
     ;
 
   if(!curlx_sztouz(rv, psent)) {
-    if(SOCKERRNO == EAGAIN || SOCKERRNO == SOCKEWOULDBLOCK) {
+    if(SOCK_EAGAIN(SOCKERRNO)) {
       result = CURLE_AGAIN;
       goto out;
     }
@@ -487,7 +485,7 @@ static CURLcode recvmmsg_packets(struct Curl_cfilter *cf,
           (SOCKERRNO == SOCKEINTR || SOCKERRNO == SOCKEMSGSIZE))
       ;
     if(mcount == -1) {
-      if(SOCKERRNO == EAGAIN || SOCKERRNO == SOCKEWOULDBLOCK) {
+      if(SOCK_EAGAIN(SOCKERRNO)) {
         CURL_TRC_CF(data, cf, "ingress, recvmmsg -> EAGAIN");
         goto out;
       }
@@ -574,7 +572,7 @@ static CURLcode recvmsg_packets(struct Curl_cfilter *cf,
           (SOCKERRNO == SOCKEINTR || SOCKERRNO == SOCKEMSGSIZE))
       ;
     if(!curlx_sztouz(rc, &nread)) {
-      if(SOCKERRNO == EAGAIN || SOCKERRNO == SOCKEWOULDBLOCK) {
+      if(SOCK_EAGAIN(SOCKERRNO)) {
         goto out;
       }
       if(!cf->connected && SOCKERRNO == SOCKECONNREFUSED) {
@@ -644,7 +642,7 @@ static CURLcode recvfrom_packets(struct Curl_cfilter *cf,
           (SOCKERRNO == SOCKEINTR || SOCKERRNO == SOCKEMSGSIZE))
       ;
     if(!curlx_sztouz(rv, &nread)) {
-      if(SOCKERRNO == EAGAIN || SOCKERRNO == SOCKEWOULDBLOCK) {
+      if(SOCK_EAGAIN(SOCKERRNO)) {
         CURL_TRC_CF(data, cf, "ingress, recvfrom -> EAGAIN");
         goto out;
       }
diff --git a/lib/vtls/rustls.c b/lib/vtls/rustls.c
index 9890f65538..39b15b889c 100644
--- a/lib/vtls/rustls.c
+++ b/lib/vtls/rustls.c
@@ -45,6 +45,12 @@
 #include "curlx/base64.h"
 #endif
 
+#if EAGAIN != EWOULDBLOCK
+#define RAW_EAGAIN(e) ((e) == EWOULDBLOCK || (e) == EAGAIN)
+#else
+#define RAW_EAGAIN(e) ((e) == EWOULDBLOCK)
+#endif
+
 struct rustls_ssl_backend_data {
   const struct rustls_client_config *config;
   struct rustls_connection *conn;
@@ -160,7 +166,7 @@ static ssize_t tls_recv_more(struct Curl_cfilter *cf,
   io_ctx.data = data;
   io_error = rustls_connection_read_tls(backend->conn, read_cb, &io_ctx,
                                         &tls_bytes_read);
-  if(io_error == EAGAIN || io_error == EWOULDBLOCK) {
+  if(RAW_EAGAIN(io_error)) {
     *err = CURLE_AGAIN;
     return -1;
   }
@@ -270,7 +276,7 @@ static CURLcode cr_flush_out(struct Curl_cfilter *cf, struct Curl_easy *data,
   while(rustls_connection_wants_write(rconn)) {
     io_error = rustls_connection_write_tls(rconn, write_cb, &io_ctx,
                                            &tlswritten);
-    if(io_error == EAGAIN || io_error == EWOULDBLOCK) {
+    if(RAW_EAGAIN(io_error)) {
       CURL_TRC_CF(data, cf, "cf_send: EAGAIN after %zu bytes",
                   tlswritten_total);
       return CURLE_AGAIN;
diff --git a/src/tool_cb_rea.c b/src/tool_cb_rea.c
index a818d0804d..b5bc53a46e 100644
--- a/src/tool_cb_rea.c
+++ b/src/tool_cb_rea.c
@@ -109,7 +109,7 @@ size_t tool_read_cb(char *buffer, size_t sz, size_t nmemb, void *userdata)
 #ifndef CURL_WINDOWS_UWP
     rc = sread(per->infd, buffer, curlx_uztosi(sz * nmemb));
     if(rc < 0) {
-      if(SOCKERRNO == SOCKEWOULDBLOCK) {
+      if(SOCK_EAGAIN(SOCKERRNO)) {
         errno = 0;
         config->readbusy = TRUE;
         return CURL_READFUNC_PAUSE;
diff --git a/tests/server/sws.c b/tests/server/sws.c
index f219bb15ab..5cb725d0c8 100644
--- a/tests/server/sws.c
+++ b/tests/server/sws.c
@@ -976,7 +976,7 @@ static int sws_send_doc(curl_socket_t sock, struct sws_httprequest *req)
 retry:
     written = swrite(sock, buffer, num);
     if(written < 0) {
-      if((SOCKEWOULDBLOCK == SOCKERRNO) || (EAGAIN == SOCKERRNO)) {
+      if(SOCK_EAGAIN(SOCKERRNO)) {
         curlx_wait_ms(10);
         goto retry;
       }
@@ -1133,8 +1133,7 @@ static int sws_get_request(curl_socket_t sock, struct sws_httprequest *req)
           logmsg("Got %zd bytes from client", got);
         }
 
-        if((got == -1) &&
-           ((SOCKERRNO == EAGAIN) || (SOCKERRNO == SOCKEWOULDBLOCK))) {
+        if((got == -1) && SOCK_EAGAIN(SOCKERRNO)) {
           int rc;
           fd_set input;
           fd_set output;
@@ -1194,7 +1193,7 @@ static int sws_get_request(curl_socket_t sock, struct sws_httprequest *req)
     else if(got < 0) {
       char errbuf[STRERROR_LEN];
       int error = SOCKERRNO;
-      if(EAGAIN == error || SOCKEWOULDBLOCK == error) {
+      if(SOCK_EAGAIN(error)) {
         /* nothing to read at the moment */
         return 0;
       }
@@ -1335,7 +1334,7 @@ static curl_socket_t connect_to(const char *ipaddr, unsigned short port)
 
   if(rc) {
     error = SOCKERRNO;
-    if((error == SOCKEINPROGRESS) || (error == SOCKEWOULDBLOCK)) {
+    if((error == SOCKEINPROGRESS) || SOCK_EAGAIN(error)) {
       fd_set output;
       struct timeval timeout = { 0 };
       timeout.tv_sec = 1; /* 1000 ms */
@@ -1353,7 +1352,7 @@ static curl_socket_t connect_to(const char *ipaddr, unsigned short port)
             error = SOCKERRNO;
           if((error == 0) || (SOCKEISCONN == error))
             goto success;
-          else if((error != SOCKEINPROGRESS) && (error != SOCKEWOULDBLOCK))
+          else if((error != SOCKEINPROGRESS) && !SOCK_EAGAIN(error))
             goto error;
         }
         else if(!rc) {
@@ -1822,7 +1821,7 @@ static curl_socket_t accept_connection(curl_socket_t sock)
 
   if(msgsock == CURL_SOCKET_BAD) {
     error = SOCKERRNO;
-    if(EAGAIN == error || SOCKEWOULDBLOCK == error) {
+    if(SOCK_EAGAIN(error)) {
       /* nothing to accept */
       return 0;
     }