diff -aurN 0001/src/unix-adapter/main.cc 0002/src/unix-adapter/main.cc
--- 0001/src/unix-adapter/main.cc
+++ 0002/src/unix-adapter/main.cc
@@ -47,6 +47,7 @@
 #include "OutputHandler.h"
 #include "Util.h"
 #include "WakeupFd.h"
+#include "path_conv.h"
 
 #define CSI "\x1b["
 
@@ -154,7 +155,12 @@
     char *tmp;
 #if defined(CYGWIN_VERSION_CYGWIN_CONV) && \
         CYGWIN_VERSION_API_MINOR >= CYGWIN_VERSION_CYGWIN_CONV
-    // MSYS2 and versions of Cygwin released after 2009 or so use this API.
+#if defined(__MSYS__)
+    size_t newSize = 256 * MAX_PATH;
+    tmp = new char[newSize + 1];
+    convert(tmp, newSize, path.c_str());
+#else
+    // Versions of Cygwin released after 2009 or so use this API.
     // The original MSYS still lacks this API.
     ssize_t newSize = cygwin_conv_path(CCP_POSIX_TO_WIN_A | CCP_RELATIVE,
                                        path.c_str(), NULL, 0);
@@ -163,6 +169,7 @@
     ssize_t success = cygwin_conv_path(CCP_POSIX_TO_WIN_A | CCP_RELATIVE,
                                        path.c_str(), tmp, newSize + 1);
     assert(success == 0);
+#endif
 #else
     // In the current Cygwin header file, this API is documented as deprecated
     // because it's restricted to paths of MAX_PATH length.  In the CVS version
@@ -173,10 +180,6 @@
     tmp = new char[MAX_PATH + path.size()];
     cygwin_conv_to_win32_path(path.c_str(), tmp);
 #endif
-    for (int i = 0; tmp[i] != '\0'; ++i) {
-        if (tmp[i] == '/')
-            tmp[i] = '\\';
-    }
     std::string ret(tmp);
     delete [] tmp;
     return ret;
diff -aurN 0001/src/unix-adapter/path_conv.cc 0002/src/unix-adapter/path_conv.cc
--- 0001/src/unix-adapter/path_conv.cc
+++ 0002/src/unix-adapter/path_conv.cc
@@ -633,7 +633,6 @@
         one_path[to-from] = '\0';
         char win32_path1[PATH_MAX + 1];
         ssize_t result = cygwin_conv_path(CCP_POSIX_TO_WIN_A|CCP_ABSOLUTE, one_path, win32_path1, PATH_MAX+1);
-        printf("called cygwin_conv_path(CCP_POSIX_TO_WIN_A,%s -> %s, in-size %d, result = %zd\n", one_path, win32_path1, PATH_MAX+1, result);
         if( result !=0 ) {
             copy_to_dst(one_path, NULL, dst, dstend);
         } else {
diff -aurN 0001/src/unix-adapter/subdir.mk 0002/src/unix-adapter/subdir.mk
--- 0001/src/unix-adapter/subdir.mk
+++ 0002/src/unix-adapter/subdir.mk
@@ -28,6 +28,7 @@
 	build/unix-adapter/unix-adapter/Util.o \
 	build/unix-adapter/unix-adapter/WakeupFd.o \
 	build/unix-adapter/unix-adapter/main.o \
+	build/unix-adapter/unix-adapter/path_conv.o \
 	build/unix-adapter/shared/DebugClient.o \
 	build/unix-adapter/shared/WinptyAssert.o \
 	build/unix-adapter/shared/WinptyVersion.o