+AC_CHECK_HEADER(CUnit/CUnit.h, [AC_DEFINE(ENABLE_TESTS, [], [whether we should compile the test-suite])])
+
+AC_CHECK_HEADER(sys/sendfile.h, [AC_DEFINE(LINUX_SENDFILE, [], [whether we have the linux sendfile api])])
+dnl TODO: we might need to check for the actual syntax....
+
+
+AC_MSG_CHECKING([whether your system knows about splice()])
+AC_TRY_COMPILE([
+#define _GNU_SOURCE
+#include <unistd.h>
+#include <fcntl.h>
+],
+[
+ ssize_t sent, pipesize;
+ int fd, SplicePipe[2];
+ pipesize = splice(fd, NULL,
+ SplicePipe[1], NULL,
+ 1,
+ SPLICE_F_MORE | SPLICE_F_MOVE|SPLICE_F_NONBLOCK);
+],
+ [
+ ok_splice=yes
+ AC_DEFINE(LINUX_SPLICE, [], [whether we have the linux splice api])
+ AC_MSG_RESULT([yes])
+ ],
+ [
+ ok_splice=no
+ AC_MSG_RESULT([no])
+ ]
+)
+
+AC_MSG_CHECKING([whether your system likes memcpy + HKEY])
+AC_TRY_COMPILE([
+#define _GNU_SOURCE
+#include <ctype.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <sys/select.h>
+#include <fcntl.h>
+#include <sys/types.h>
+
+#include "lib/libcitadel.h"
+],
+[
+ char foo[22];
+ memcpy(foo, HKEY("foo"));
+
+],
+ [
+
+ AC_MSG_RESULT([yes])
+ ],
+ [
+ AC_DEFINE(UNDEF_MEMCPY, [], [whether we need to undefine memcpy])
+ AC_MSG_RESULT([no])
+ ]
+)
+
+