diff --git a/lib/std/mem.zig b/lib/std/mem.zig
index d8b3872eb0be27f79fa66b3805f7cb567e57be10..a679291dba1bcae6e79286ad3b7b199562f68695 100644
--- a/lib/std/mem.zig
+++ b/lib/std/mem.zig
@@ -269,6 +269,39 @@ pub fn copyBackwards(comptime T: type, dest: []T, source: []const T) void {
     }
 }
 
+/// Copy `source` into `dest`, excluding the sentinel.
+///
+/// Asserts no overlap. Asserts `dest.len` greater or equal to source len. Returns number of elements copied,
+/// not counting the sentinel.
+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);
+}
+
+/// Copy `source` into `dest`, including the sentinel.
+///
+/// Asserts no overlap. Asserts `dest.len` greater or equal to source len, including room for the sentinel.
+/// Returns number of elements copied, including the sentinel.
+pub fn copySentinelInclusive(comptime T: type, comptime s: T, dest: []T, source: [*:s]const T) usize {
+    const i = findSentinel(T, s, source) + 1;
+    @memcpy(dest[0..i], source[0..i]);
+    return i;
+}
+
+test copySentinelInclusive {
+    var dst: [12]u8 = @splat(0xff);
+    const n = copySentinelInclusive(u8, 0, &dst, "hello this\x00is my null-terminated string");
+    try testing.expectEqualStrings("hello this\x00\xff", &dst);
+    try testing.expectEqual(n, 11);
+}
 /// 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
@@ -733,6 +766,19 @@ test lessThan {
     try testing.expect(lessThan(u8, "", "a"));
 }
 
+/// Returns `true` if `lhs < rhs`; `false` otherwise, operating on null-terminated arrays.
+pub fn lessThanZ(comptime T: type, lhs: [*:0]const T, rhs: [*:0]const T) bool {
+    return orderZ(T, lhs, rhs) == .lt;
+}
+
+test lessThanZ {
+    try testing.expect(lessThanZ(u8, "abcd", "bee"));
+    try testing.expect(!lessThanZ(u8, "abc", "abc"));
+    try testing.expect(lessThanZ(u8, "abc", "abc0"));
+    try testing.expect(!lessThanZ(u8, "", ""));
+    try testing.expect(lessThanZ(u8, "", "a"));
+}
+
 const use_vectors = switch (builtin.zig_backend) {
     // These backends don't support vectors yet.
     .stage2_aarch64,