code review 7232060: cmd/dist: fix code example in README

src/cmd/dist/README

 This program, dist, is the bootstrapping tool for the Go distribution.
 It takes care of building the C programs (like the Go compiler) and
 the initial bootstrap copy of the go tool.  It also serves as a catch-all
 to replace odd jobs previously done with shell scripts.
 
 Dist is itself written in very simple C.  All interaction with C libraries,
 even standard C libraries, is confined to a single system-specific file
 (plan9.c, unix.c, windows.c), to aid portability.  Functionality needed
 by other files should be exposed via the portability layer.  Functions
 in the portability layer begin with an x prefix when they would otherwise
@@ skipping 13 matching lines @@
                 Buf b1, b2;
                 Vec v1;
 ················
                 binit(&b1);
                 binit(&b2);
                 vinit(&v1);
 ················
                 ... main code ...
                 bprintf(&b1, "hello, world");
                 vadd(&v1, bstr(&b1));  // v1 takes a copy of its argument
-                bprintf(&b1, "another string");
-                vadd(&v1, bstr(&b1));  // v1 now has two strings
+                bprintf(&b2, "another string");
+                vadd(&v1, bstr(&b2));  // v1 now has two strings
 ················
                 bfree(&b1);
                 bfree(&b2);
                 vfree(&v1);
         }
 ········
 The binit/vinit calls prepare a buffer or vector for use, initializing the·
 data structures, and the bfree/vfree calls free any memory they are still
 holding onto.  Use of this idiom gives us lexically scoped allocations.