1 files changed, 12 insertions, 0 deletions
diff --git a/test/e2e_harness.zig b/test/e2e_harness.zig
index 5a181b78..eaa19b43 100644
--- a/test/e2e_harness.zig
+++ b/test/e2e_harness.zig
@@ -366,6 +366,18 @@ pub const Harness = struct {
 };
 
 /// Write a file (helper for test setup, raw libc).
+pub fn appendFile(path: [*:0]const u8, data: []const u8) !void {
+    const fd = libc.open(path, .{ .ACCMODE = .WRONLY, .CREAT = true, .APPEND = true }, @as(libc.mode_t, 0o644));
+    if (fd < 0) return error.OpenFailed;
+    defer _ = libc.close(fd);
+    var off: usize = 0;
+    while (off < data.len) {
+        const w = libc.write(fd, data[off..].ptr, data.len - off);
+        if (w <= 0) break;
+        off += @intCast(w);
+    }
+}
+
 pub fn writeFile(path: [*:0]const u8, data: []const u8) !void {
     const fd = libc.open(path, .{ .ACCMODE = .WRONLY, .CREAT = true, .TRUNC = true }, @as(libc.mode_t, 0o644));
     if (fd < 0) return error.OpenFailed;