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diff --git a/src/libs/3rdparty/winpty/misc/VeryLargeRead.cc b/src/libs/3rdparty/winpty/misc/VeryLargeRead.cc
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+++ b/src/libs/3rdparty/winpty/misc/VeryLargeRead.cc
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+//
+// 2015-09-25
+// I measured these limits on the size of a single ReadConsoleOutputW call.
+// The limit seems to more-or-less disppear with Windows 8, which is the first
+// OS to stop using ALPCs for console I/O.  My guess is that the new I/O
+// method does not use the 64KiB shared memory buffer that the ALPC method
+// uses.
+//
+// I'm guessing the remaining difference between Windows 8/8.1 and Windows 10
+// might be related to the 32-vs-64-bitness.
+//
+// Client OSs
+//
+// Windows XP 32-bit VM ==> up to 13304 characters
+//  - 13304x1 works, but 13305x1 fails instantly
+// Windows 7 32-bit VM ==> between 16-17 thousand characters
+//  - 16000x1 works, 17000x1 fails instantly
+//  - 163x100 *crashes* conhost.exe but leaves VeryLargeRead.exe running
+// Windows 8 32-bit VM ==> between 240-250 million characters
+//  - 10000x24000 works, but 10000x25000 does not
+// Windows 8.1 32-bit VM ==> between 240-250 million characters
+//  - 10000x24000 works, but 10000x25000 does not
+// Windows 10 64-bit VM ==> no limit (tested to 576 million characters)
+//  - 24000x24000 works
+//  - `ver` reports [Version 10.0.10240], conhost.exe and ConhostV1.dll are
+//    10.0.10240.16384 for file and product version.  ConhostV2.dll is
+//    10.0.10240.16391 for file and product version.
+//
+// Server OSs
+//
+// Windows Server 2008 64-bit VM ==> 14300-14400 characters
+//  - 14300x1 works, 14400x1 fails instantly
+//  - This OS does not have conhost.exe.
+//  - `ver` reports [Version 6.0.6002]
+// Windows Server 2008 R2 64-bit VM ==> 15600-15700 characters
+//  - 15600x1 works, 15700x1 fails instantly
+//  - This OS has conhost.exe, and procexp.exe reveals console ALPC ports in
+//    use in conhost.exe.
+//  - `ver` reports [Version 6.1.7601], conhost.exe is 6.1.7601.23153 for file
+//    and product version.
+// Windows Server 2012 64-bit VM ==> at least 100 million characters
+//  - 10000x10000 works (VM had only 1GiB of RAM, so I skipped larger tests)
+//  - This OS has Windows 8's task manager and procexp.exe reveals the same
+//    lack of ALPC ports and the same \Device\ConDrv\* files as Windows 8.
+//  - `ver` reports [Version 6.2.9200], conhost.exe is 6.2.9200.16579 for file
+//    and product version.
+//
+// To summarize:
+//
+// client-OS    server-OS               notes
+// ---------------------------------------------------------------------------
+// XP           Server 2008             CSRSS, small reads
+// 7            Server 2008 R2          ALPC-to-conhost, small reads
+// 8, 8.1       Server 2012             new I/O interface, large reads allowed
+// 10           <no server OS yet>      enhanced console w/rewrapping
+//
+// (Presumably, Win2K, Vista, and Win2K3 behave the same as XP.  conhost.exe
+// was announced as a Win7 feature.)
+//
+
+#include <windows.h>
+#include <assert.h>
+#include <vector>
+
+#include "TestUtil.cc"
+
+int main(int argc, char *argv[]) {
+    long long width = 9000;
+    long long height = 9000;
+
+    assert(argc >= 1);
+    if (argc == 4) {
+        width = atoi(argv[2]);
+        height = atoi(argv[3]);
+    } else {
+        if (argc == 3) {
+            width = atoi(argv[1]);
+            height = atoi(argv[2]);
+        }
+        wchar_t args[1024];
+        swprintf(args, 1024, L"CHILD %lld %lld", width, height);
+        startChildProcess(args);
+        return 0;
+    }
+
+    const HANDLE conout = GetStdHandle(STD_OUTPUT_HANDLE);
+
+    setWindowPos(0, 0, 1, 1);
+    setBufferSize(width, height);
+    setWindowPos(0, 0, std::min(80LL, width), std::min(50LL, height));
+
+    setCursorPos(0, 0);
+    printf("A");
+    fflush(stdout);
+    setCursorPos(width - 2, height - 1);
+    printf("B");
+    fflush(stdout);
+
+    trace("sizeof(CHAR_INFO) = %d", (int)sizeof(CHAR_INFO));
+
+    trace("Allocating buffer...");
+    CHAR_INFO *buffer = new CHAR_INFO[width * height];
+    assert(buffer != NULL);
+    memset(&buffer[0], 0, sizeof(CHAR_INFO));
+    memset(&buffer[width * height - 2], 0, sizeof(CHAR_INFO));
+
+    COORD bufSize = { width, height };
+    COORD bufCoord = { 0, 0 };
+    SMALL_RECT readRegion = { 0, 0, width - 1, height - 1 };
+    trace("ReadConsoleOutputW: calling...");
+    BOOL success = ReadConsoleOutputW(conout, buffer, bufSize, bufCoord, &readRegion);
+    trace("ReadConsoleOutputW: success=%d", success);
+
+    assert(buffer[0].Char.UnicodeChar == L'A');
+    assert(buffer[width * height - 2].Char.UnicodeChar == L'B');
+    trace("Top-left and bottom-right characters read successfully!");
+
+    Sleep(30000);
+
+    delete [] buffer;
+    return 0;
+}