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Diffstat (limited to 'reference/C/CONTRIB/SNIP/getseg.c')
-rwxr-xr-xreference/C/CONTRIB/SNIP/getseg.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/getseg.c b/reference/C/CONTRIB/SNIP/getseg.c
new file mode 100755
index 0000000..ff35e5e
--- /dev/null
+++ b/reference/C/CONTRIB/SNIP/getseg.c
@@ -0,0 +1,49 @@
+/*
+** GETSEG.C - How to get the memory segment of an object
+**
+** public domain demo by Bob Stout
+*/
+
+#include <stdio.h>
+#include <dos.h>
+
+#ifdef __TURBOC__
+ #define FAR far
+#else
+ #define FAR _far
+#endif
+
+#define GetSeg(obj) (unsigned)((unsigned long)(((void FAR *)(obj))) >> 16)
+#define GetOfs(obj) (unsigned)((unsigned long)(((void FAR *)(obj))) & 0xffff)
+
+int dummyv = 0;
+
+int dummyf(void)
+{
+ return dummyv;
+}
+
+void main(void)
+{
+ struct SREGS sregs;
+
+ segread (&sregs);
+ printf("DS = %04X, CS = %04X\n", sregs.ds, sregs.cs);
+
+#if defined(__ZTC__)
+ printf("&dummyv = %lp, dummyf = %lp\n\n",
+#else
+ printf("&dummyv = %Fp, dummyf = %Fp\n\n",
+#endif
+
+#if defined(__ZTC__) || defined(__TURBOC__)
+ (int FAR *)&dummyv, (int (FAR *)())dummyf);
+#else /* MSC doesn't allow casting near function pointers to far */
+ (int FAR *)&dummyv, dummyf);
+#endif
+
+ printf("GetSeg(dummyv) = %04X, GetSeg(dummyf) = %04X\n",
+ GetSeg(&dummyv), GetSeg(dummyf));
+ printf("GetOfs(dummyv) = %04X, GetOfs(dummyf) = %04X\n",
+ GetOfs(&dummyv), GetOfs(dummyf));
+}