new file mode 100644
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+++ b/m4/csharpcomp.m4
@@ -0,0 +1,70 @@
+# csharpcomp.m4 serial 5 (gettext-0.15)
+dnl Copyright (C) 2003-2005 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+# Prerequisites of csharpcomp.sh.
+# Sets HAVE_CSHARPCOMP to nonempty if csharpcomp.sh will work.
+
+AC_DEFUN([gt_CSHARPCOMP],
+[
+  AC_REQUIRE([gt_CSHARP_CHOICE])
+  AC_MSG_CHECKING([for C[#] compiler])
+  HAVE_CSHARPCOMP=1
+  pushdef([AC_MSG_CHECKING],[:])dnl
+  pushdef([AC_CHECKING],[:])dnl
+  pushdef([AC_MSG_RESULT],[:])dnl
+  AC_CHECK_PROG(HAVE_CSCC_IN_PATH, cscc, yes)
+  AC_CHECK_PROG(HAVE_MCS_IN_PATH, mcs, yes)
+  AC_CHECK_PROG(HAVE_CSC_IN_PATH, csc, yes)
+  popdef([AC_MSG_RESULT])dnl
+  popdef([AC_CHECKING])dnl
+  popdef([AC_MSG_CHECKING])dnl
+  for impl in "$CSHARP_CHOICE" pnet mono sscli no; do
+    case "$impl" in
+      pnet)
+        if test -n "$HAVE_CSCC_IN_PATH" \
+           && cscc --version >/dev/null 2>/dev/null \
+           && (
+             # See if pnetlib is well installed.
+             echo 'class ConfTest { static void Main() { } }' > conftest.cs
+             cscc -o conftest.exe conftest.cs 2>/dev/null
+             error=$?
+             rm -f conftest.cs conftest.exe
+             exit $error
+            ); then
+          HAVE_CSCC=1
+          ac_result="cscc"
+          break
+        fi
+        ;;
+      mono)
+        if test -n "$HAVE_MCS_IN_PATH" \
+           && mcs --version >/dev/null 2>/dev/null; then
+          HAVE_MCS=1
+          ac_result="mcs"
+          break
+        fi
+        ;;
+      sscli)
+        if test -n "$HAVE_CSC_IN_PATH" \
+           && csc -help >/dev/null 2>/dev/null \
+           && { if csc -help 2>/dev/null | grep -i chicken > /dev/null; then false; else true; fi; }; then
+          HAVE_CSC=1
+          ac_result="csc"
+          break
+        fi
+        ;;
+      no)
+        HAVE_CSHARPCOMP=
+        ac_result="no"
+        break
+        ;;
+    esac
+  done
+  AC_MSG_RESULT([$ac_result])
+  AC_SUBST(HAVE_CSCC)
+  AC_SUBST(HAVE_MCS)
+  AC_SUBST(HAVE_CSC)
+])