Fix the detection of installed RAM on QNX.

The earlier version compiled but didn't actually work
since sysconf(_SC_PHYS_PAGES) always fails (or so I was told).

Thanks to Ole André Vadla Ravnås for the patch and testing.

m4/tuklib_physmem.m4

diff --git a/m4/tuklib_physmem.m4 b/m4/tuklib_physmem.m4
index ea02208..8a57ca2 100644
--- a/m4/tuklib_physmem.m4
+++ b/m4/tuklib_physmem.m4
@@ -10,8 +10,8 @@
 #
 #   Supported methods:
 #
-#     - Windows (including Cygwin), OS/2, DJGPP (DOS), and OpenVMS have
-#       operating-system specific functions.
+#     - Windows (including Cygwin), OS/2, DJGPP (DOS), OpenVMS, AROS,
+#       and QNX have operating-system specific functions.
 #
 #     - AIX has _system_configuration.physmem.
 #
@@ -54,7 +54,7 @@
 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
 #if defined(_WIN32) || defined(__CYGWIN__) || defined(__OS2__) \
 		|| defined(__DJGPP__) || defined(__VMS) \
-		|| defined(AMIGA) || defined(__AROS__)
+		|| defined(AMIGA) || defined(__AROS__) || defined(__QNX__)
 int main(void) { return 0; }
 #else
 compile error

src/common/tuklib_physmem.c

diff --git a/src/common/tuklib_physmem.c b/src/common/tuklib_physmem.c
index 3cc7d12..cd2437d 100644
--- a/src/common/tuklib_physmem.c
+++ b/src/common/tuklib_physmem.c
@@ -37,7 +37,10 @@
 #	define __USE_INLINE__
 #	include <proto/exec.h>
 
-// AIX
+#elif defined(__QNX__)
+#	include <sys/syspage.h>
+#	include <string.h>
+
 #elif defined(TUKLIB_PHYSMEM_AIX)
 #	include <sys/systemcfg.h>
 
@@ -126,6 +129,15 @@
 #elif defined(AMIGA) || defined(__AROS__)
 	ret = AvailMem(MEMF_TOTAL);
 
+#elif defined(__QNX__)
+	const struct asinfo_entry *entries = SYSPAGE_ENTRY(asinfo);
+	size_t count = SYSPAGE_ENTRY_SIZE(asinfo) / sizeof(struct asinfo_entry);
+	const char *strings = SYSPAGE_ENTRY(strings)->data;
+
+	for (size_t i = 0; i < count; ++i)
+		if (strcmp(strings + entries[i].name, "ram") == 0)
+			ret += entries[i].end - entries[i].start + 1;
+
 #elif defined(TUKLIB_PHYSMEM_AIX)
 	ret = _system_configuration.physmem;