diff --git a/tests/data/Makefile.inc b/tests/data/Makefile.inc
index 13211651f7..ae908f23d7 100644
--- a/tests/data/Makefile.inc
+++ b/tests/data/Makefile.inc
@@ -225,7 +225,7 @@ test1916 test1917 test1918 test1919 \
\
test1933 test1934 test1935 test1936 test1937 test1938 test1939 test1940 \
test1941 test1942 test1943 test1944 test1945 test1946 test1947 test1948 \
-test1955 test1956 test1957 test1958 test1959 \
+test1955 test1956 test1957 test1958 test1959 test1960 \
\
test2000 test2001 test2002 test2003 test2004 \
\
diff --git a/tests/data/test1960 b/tests/data/test1960
new file mode 100644
index 0000000000..101e1e1529
--- /dev/null
+++ b/tests/data/test1960
@@ -0,0 +1,52 @@
+
+
+
+HTTP
+CURLOPT_SOCKOPTFUNCTION
+CURL_SOCKOPT_ALREADY_CONNECTED
+
+
+
+# Server-side
+
+
+HTTP/1.1 200 OK
+Date: Thu, 09 Nov 2010 14:49:00 GMT
+Server: test-server/fake
+Content-Type: text/html
+Content-Length: 0
+
+
+
+
+# Client-side
+
+
+lib%TESTNUMBER check
+
+
+http
+
+
+
+application hands over already connected socket
+
+
+lib%TESTNUMBER
+
+
+
+http://%HOSTIP:%HTTPPORT/file %HOSTIP %HTTPPORT
+
+
+
+# Verify data after the test has been "shot"
+
+
+GET /file HTTP/1.1
+Host: %HOSTIP:%HTTPPORT
+Accept: */*
+
+
+
+
diff --git a/tests/libtest/Makefile.inc b/tests/libtest/Makefile.inc
index 72bd3456bf..a82df608ed 100644
--- a/tests/libtest/Makefile.inc
+++ b/tests/libtest/Makefile.inc
@@ -69,6 +69,7 @@ noinst_PROGRAMS = chkhostname libauthretry libntlmconnect \
lib1915 lib1916 lib1917 lib1918 lib1919 \
lib1933 lib1934 lib1935 lib1936 lib1937 lib1938 lib1939 lib1940 \
lib1945 lib1946 lib1947 lib1948 lib1955 lib1956 lib1957 lib1958 lib1959 \
+ lib1960 \
lib2301 lib2302 lib2304 lib2305 \
lib2402 \
lib2502 \
@@ -791,6 +792,9 @@ lib1959_SOURCES = lib1959.c $(SUPPORTFILES) $(TESTUTIL) $(WARNLESS)
lib1959_LDADD = $(TESTUTIL_LIBS)
lib1959_CPPFLAGS = $(AM_CPPFLAGS)
+lib1960_SOURCES = lib1960.c $(SUPPORTFILES)
+lib1960_LDADD = $(TESTUTIL_LIBS)
+
lib2301_SOURCES = lib2301.c $(SUPPORTFILES)
lib2301_LDADD = $(TESTUTIL_LIBS)
diff --git a/tests/libtest/lib1960.c b/tests/libtest/lib1960.c
new file mode 100644
index 0000000000..fc2f4b0af7
--- /dev/null
+++ b/tests/libtest/lib1960.c
@@ -0,0 +1,155 @@
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) Daniel Stenberg, , et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * SPDX-License-Identifier: curl
+ *
+ ***************************************************************************/
+#include "test.h"
+
+#ifdef HAVE_INET_PTON
+
+#ifdef WIN32
+#include
+#include
+#include
+#endif
+
+#ifdef HAVE_NETINET_IN_H
+#include
+#endif
+#ifdef HAVE_SYS_SOCKET_H
+#include
+#endif
+#ifdef HAVE_ARPA_INET_H
+#include
+#endif
+
+#include "memdebug.h"
+
+/* to prevent libcurl from closing our socket */
+static int closesocket_cb(void *clientp, curl_socket_t item)
+{
+ (void)clientp;
+ (void)item;
+ return 0;
+}
+
+/* provide our own socket */
+static curl_socket_t socket_cb(void *clientp,
+ curlsocktype purpose,
+ struct curl_sockaddr *address)
+{
+ int s = *(int *)clientp;
+ (void)purpose;
+ (void)address;
+ return (curl_socket_t)s;
+}
+
+/* tell libcurl the socket is connected */
+static int sockopt_cb(void *clientp,
+ curl_socket_t curlfd,
+ curlsocktype purpose)
+{
+ (void)clientp;
+ (void)curlfd;
+ (void)purpose;
+ return CURL_SOCKOPT_ALREADY_CONNECTED;
+}
+
+/* Expected args: URL IP PORT */
+int test(char *URL)
+{
+ CURL *curl = NULL;
+ CURLcode res = TEST_ERR_MAJOR_BAD;
+ int status;
+ curl_socket_t client_fd = CURL_SOCKET_BAD;
+ struct sockaddr_in serv_addr;
+ unsigned short port;
+
+ if(!strcmp("check", URL))
+ return 0; /* no output makes it not skipped */
+
+ port = (unsigned short)atoi(libtest_arg3);
+
+ if(curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
+ fprintf(stderr, "curl_global_init() failed\n");
+ return TEST_ERR_MAJOR_BAD;
+ }
+
+ /*
+ * This code connects to the TCP port "manually" so that we then can hand
+ * over this socket as "already connected" to libcurl and make sure that
+ * this works.
+ */
+ client_fd = socket(AF_INET, SOCK_STREAM, 0);
+ if(client_fd == CURL_SOCKET_BAD) {
+ fprintf(stderr, "socket creation error\n");
+ goto test_cleanup;
+ }
+
+ serv_addr.sin_family = AF_INET;
+ serv_addr.sin_port = htons(port);
+
+ if(inet_pton(AF_INET, libtest_arg2, &serv_addr.sin_addr) <= 0) {
+ fprintf(stderr, "inet_pton failed\n");
+ goto test_cleanup;
+ }
+
+ status = connect(client_fd, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
+ if(status < 0) {
+ fprintf(stderr, "connection failed\n");
+ goto test_cleanup;
+ }
+
+ curl = curl_easy_init();
+ if(!curl) {
+ fprintf(stderr, "curl_easy_init() failed\n");
+ goto test_cleanup;
+ }
+
+ test_setopt(curl, CURLOPT_VERBOSE, 1L);
+ test_setopt(curl, CURLOPT_OPENSOCKETFUNCTION, socket_cb);
+ test_setopt(curl, CURLOPT_OPENSOCKETDATA, &client_fd);
+ test_setopt(curl, CURLOPT_SOCKOPTFUNCTION, sockopt_cb);
+ test_setopt(curl, CURLOPT_SOCKOPTDATA, NULL);
+ test_setopt(curl, CURLOPT_CLOSESOCKETFUNCTION, closesocket_cb);
+ test_setopt(curl, CURLOPT_CLOSESOCKETDATA, NULL);
+ test_setopt(curl, CURLOPT_VERBOSE, 1L);
+ test_setopt(curl, CURLOPT_HEADER, 1L);
+ test_setopt(curl, CURLOPT_URL, URL);
+
+ res = curl_easy_perform(curl);
+
+test_cleanup:
+ if(client_fd != CURL_SOCKET_BAD)
+ sclose(client_fd);
+ curl_easy_cleanup(curl);
+ curl_global_cleanup();
+
+ return res;
+}
+#else
+int test(char *URL)
+{
+ (void)URL;
+ printf("lacks inet_pton\n");
+ return 0;
+}
+#endif