Data commit

Task/Address-of-a-variable/Tcl/address-of-a-variable-1.tcl

@@ -0,0 +1,21 @@
+package require critcl
+# This code assumes an ILP32 architecture, like classic x86 or VAX.
+critcl::cproc peek {int addr} int {
+    union {
+       int i;
+       int *a;
+    } u;
+
+    u.i = addr;
+    return *u.a;
+}
+critcl::cproc poke {int addr int value} void {
+    union {
+        int i;
+        int *a;
+    } u;
+
+    u.i = addr;
+    *u.a = value;
+}
+package provide poker 1.0

Task/Address-of-a-variable/Tcl/address-of-a-variable-2.tcl

@@ -0,0 +1,7 @@
+package require poker
+
+# Increment a memory location; this will probably crash if you try for real.
+# We don't define how to get a good address, but it's not usually a problem
+# for embedded programming...
+set where 0x12340
+poke $where [expr {[peek $where] + 1}]