diff --git a/lib/std/mem.zig b/lib/std/mem.zig
index d8b3872eb0be27f79fa66b3805f7cb567e57be10..24daa4a508f6fde819c5d558a5e3dd81f685c3b1 100644
--- a/lib/std/mem.zig
+++ b/lib/std/mem.zig
@@ -269,6 +269,21 @@ pub fn copyBackwards(comptime T: type, dest: []T, source: []const T) void {
     }
 }
 
+/// Copy `source` into `dest`. Asserts no overlap. Asserts `dest.len` greater or equal to source len. Returns
+/// number of elements copied. Sentinel is not copied.
+pub fn copySentinel(comptime T: type, comptime s: T, dest: []T, source: [*:s]const T) usize {
+    const i = findSentinel(T, s, source);
+    @memcpy(dest[0..i], source[0..i]);
+    return i;
+}
+
+test copySentinel {
+    var dst: [11]u8 = @splat(0xff);
+    const n = copySentinel(u8, 0, &dst, "hello this\x00is my null-terminated string");
+    try testing.expectEqualStrings("hello this\xff", &dst);
+    try testing.expectEqual(n, 10);
+}
+
 /// Generally, Zig users are encouraged to explicitly initialize all fields of a struct explicitly rather than using this function.
 /// However, it is recognized that there are sometimes use cases for initializing all fields to a "zero" value. For example, when
 /// interfacing with a C API where this practice is more common and relied upon. If you are performing code review and see this