A look line takes `?re?` after its colon, as addr does

`file:?foo?`, `@p5:?foo?` and `:?foo?` were not taken for addresses (the
first character had to be one of `0-9+-/$.#,;`), so they went the path
way and found nothing.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

2 files changed, 4 insertions, 1 deletions

diff --git a/src/look.zig b/src/look.zig
index cfebd42d..92e711fa 100644
--- a/src/look.zig
+++ b/src/look.zig
@@ -1266,7 +1266,7 @@ fn addressed(tok: []const u8) ?struct { path: []const u8, expr: []const u8 } {
     // pattern in the address may (`calc.py:/return a/`).
     if (std.mem.indexOfAny(u8, tok[0..colon], " \t") != null) return null;
     if (std.mem.indexOfAny(u8, expr, " \t") != null and std.mem.indexOfAny(u8, expr, "/?") == null) return null;
-    if (expr.len == 0 or std.mem.indexOfScalar(u8, "0123456789+-/$.#,;", expr[0]) == null) return null;
+    if (expr.len == 0 or std.mem.indexOfScalar(u8, "0123456789+-/?$.#,;", expr[0]) == null) return null;
     if (std.ascii.isDigit(expr[0])) {
         const pl = parsePathLine(tok);
         if (pl.at.line != 0 and pl.end == tok.len) return null;
diff --git a/src/ninep/ctl.zig b/src/ninep/ctl.zig
index acb1b934..02201de0 100644
--- a/src/ninep/ctl.zig
+++ b/src/ninep/ctl.zig
@@ -1951,6 +1951,9 @@ test "@p<serial>:<address> takes any sam address; a miss and an unknown serial a
         .{ .addr = "#12,#15", .want = "         12          15 " },
         .{ .addr = "$", .want = "         16          16 " },
         .{ .addr = "1,2", .want = "          0          16 " },
+        // Backward, as in addr: from the dot's start, wrapping to the last.
+        .{ .addr = "?foo?", .want = "          6           9 " },
+        .{ .addr = "$-?y?", .want = "         10          11 " },
     }) |c| {
         var line: [64]u8 = undefined;
         try testing.expectEqual(Status.ok, wr(p, root, try std.fmt.bufPrint(&line, "@p{d}:{s}\n", .{ serial, c.addr })).reply.status);