Add gnulib `select' module.

Should fix fport_input_waiting when neither poll nor select nor FIONREAD
are available, which is the case on MinGW.  Thanks to Eli Zaretskii for
the report.

lib/Makefile.am

@@ -21,7 +21,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --dir=. --local-dir=gnulib-local --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --lgpl=3 --no-conditional-dependencies --libtool --macro-prefix=gl --no-vc-files accept alignof alloca-opt announce-gen autobuild bind byteswap canonicalize-lgpl ceil clock-time close connect dirfd duplocale environ extensions flock floor fpieee frexp full-read full-write func gendocs getaddrinfo getpeername getsockname getsockopt git-version-gen gitlog-to-changelog gnu-web-doc-update gnupload havelib iconv_open-utf inet_ntop inet_pton isinf isnan ldexp lib-symbol-versions lib-symbol-visibility libunistring listen localcharset locale log1p maintainer-makefile malloc-gnu malloca nl_langinfo nproc open pipe2 putenv recv recvfrom regex rename send sendto setenv setsockopt shutdown socket stat-time stdlib strftime striconveh string sys_stat trunc verify vsnprintf warnings wchar
+# Reproduce by: gnulib-tool --import --dir=. --local-dir=gnulib-local --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --lgpl=3 --no-conditional-dependencies --libtool --macro-prefix=gl --no-vc-files accept alignof alloca-opt announce-gen autobuild bind byteswap canonicalize-lgpl ceil clock-time close connect dirfd duplocale environ extensions flock floor fpieee frexp full-read full-write func gendocs getaddrinfo getpeername getsockname getsockopt git-version-gen gitlog-to-changelog gnu-web-doc-update gnupload havelib iconv_open-utf inet_ntop inet_pton isinf isnan ldexp lib-symbol-versions lib-symbol-visibility libunistring listen localcharset locale log1p maintainer-makefile malloc-gnu malloca nl_langinfo nproc open pipe2 putenv recv recvfrom regex rename select send sendto setenv setsockopt shutdown socket stat-time stdlib strftime striconveh string sys_stat trunc verify vsnprintf warnings wchar
 
 AUTOMAKE_OPTIONS = 1.5 gnits subdir-objects
 
@@ -62,6 +62,7 @@ libgnu_la_LDFLAGS += $(ISNANL_LIBM)
 libgnu_la_LDFLAGS += $(LDEXP_LIBM)
 libgnu_la_LDFLAGS += $(LIBSOCKET)
 libgnu_la_LDFLAGS += $(LIB_CLOCK_GETTIME)
+libgnu_la_LDFLAGS += $(LIB_SELECT)
 libgnu_la_LDFLAGS += $(LOG1P_LIBM)
 libgnu_la_LDFLAGS += $(LOG_LIBM)
 libgnu_la_LDFLAGS += $(LTLIBICONV)
@@ -87,6 +88,17 @@ EXTRA_DIST += alignof.h
 
 ## end   gnulib module alignof
 
+## begin gnulib module alloca
+
+
+libgnu_la_LIBADD += @LTALLOCA@
+libgnu_la_DEPENDENCIES += @LTALLOCA@
+EXTRA_DIST += alloca.c
+
+EXTRA_libgnu_la_SOURCES += alloca.c
+
+## end   gnulib module alloca
+
 ## begin gnulib module alloca-opt
 
 BUILT_SOURCES += $(ALLOCA_H)
@@ -371,6 +383,15 @@ EXTRA_DIST += dosname.h
 
 ## end   gnulib module dosname
 
+## begin gnulib module dup2
+
+
+EXTRA_DIST += dup2.c
+
+EXTRA_libgnu_la_SOURCES += dup2.c
+
+## end   gnulib module dup2
+
 ## begin gnulib module duplocale
 
 
@@ -1560,6 +1581,15 @@ EXTRA_DIST += same-inode.h
 
 ## end   gnulib module same-inode
 
+## begin gnulib module select
+
+
+EXTRA_DIST += select.c
+
+EXTRA_libgnu_la_SOURCES += select.c
+
+## end   gnulib module select
+
 ## begin gnulib module send
 
 
@@ -2314,6 +2344,40 @@ EXTRA_DIST += sys_file.in.h
 
 ## end   gnulib module sys_file
 
+## begin gnulib module sys_select
+
+BUILT_SOURCES += sys/select.h
+
+# We need the following in order to create <sys/select.h> when the system
+# doesn't have one that works with the given compiler.
+sys/select.h: sys_select.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(WARN_ON_USE_H)
+	$(AM_V_at)$(MKDIR_P) sys
+	$(AM_V_GEN)rm -f $@-t $@ && \
+	{ echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
+	  sed -e 's|@''GUARD_PREFIX''@|GL|g' \
+	      -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
+	      -e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
+	      -e 's|@''PRAGMA_COLUMNS''@|@PRAGMA_COLUMNS@|g' \
+	      -e 's|@''NEXT_SYS_SELECT_H''@|$(NEXT_SYS_SELECT_H)|g' \
+	      -e 's|@''HAVE_SYS_SELECT_H''@|$(HAVE_SYS_SELECT_H)|g' \
+	      -e 's/@''GNULIB_PSELECT''@/$(GNULIB_PSELECT)/g' \
+	      -e 's/@''GNULIB_SELECT''@/$(GNULIB_SELECT)/g' \
+	      -e 's|@''HAVE_WINSOCK2_H''@|$(HAVE_WINSOCK2_H)|g' \
+	      -e 's|@''HAVE_PSELECT''@|$(HAVE_PSELECT)|g' \
+	      -e 's|@''REPLACE_PSELECT''@|$(REPLACE_PSELECT)|g' \
+	      -e 's|@''REPLACE_SELECT''@|$(REPLACE_SELECT)|g' \
+	      -e '/definitions of _GL_FUNCDECL_RPL/r $(CXXDEFS_H)' \
+	      -e '/definition of _GL_WARN_ON_USE/r $(WARN_ON_USE_H)' \
+	      < $(srcdir)/sys_select.in.h; \
+	} > $@-t && \
+	mv $@-t $@
+MOSTLYCLEANFILES += sys/select.h sys/select.h-t
+MOSTLYCLEANDIRS += sys
+
+EXTRA_DIST += sys_select.in.h
+
+## end   gnulib module sys_select
+
 ## begin gnulib module sys_socket
 
 BUILT_SOURCES += sys/socket.h