diff --git a/ka/crt/sys.k b/ka/crt/sys.k
index 1064614..0e6b322 100644
--- a/ka/crt/sys.k
+++ b/ka/crt/sys.k
@@ -1,10 +1,22 @@
 ; The OS/K Team licenses this file to you under the MIT license.
 ; See the LICENSE file in the project root for more information.
 
+; FIND syscalls
+;
+; Find file on disk
+;
+; IN
+;   ax0 = address of name buffer
+;   ax1 = size of name buffer
+;
+; OUT
+;   rax = # of bytes written in name buffer
+;   rdx = size of file
+;
+;
+Sys.FindFirst := 0x20
+Sys.FindNext := 0x21
+
 ; Halt mode
 Sys.HLT := 0x99
 
-; DIR syscall
-Sys.DIR := 0x100
-
-
diff --git a/ka/doskrnl.k b/ka/doskrnl.k
index f3c79cd..17e40ac 100644
--- a/ka/doskrnl.k
+++ b/ka/doskrnl.k
@@ -16,10 +16,9 @@ start:
 
     call main
 
-    mov ax0, Sys.DIR
-    trap 0
+    call CMD.builtins.dir
 
-    mov ax0, Sys.HLT
+    mov rax, Sys.HLT
     trap 0
 
     crash
diff --git a/ka/sys/intr/common.k b/ka/sys/intr/common.k
index 0e6cba4..d48e47c 100644
--- a/ka/sys/intr/common.k
+++ b/ka/sys/intr/common.k
@@ -6,14 +6,25 @@ TrapHandlers.prolog:
     mov q[rbp-8], r11
     mov q[rbp-16], r12
     mov q[rbp-24], r13
+    xor rdx, rdx
 
-    jmp rax ; go back
+    jmp rcx ; go back
 
 TrapHandlers.epilog:
     mov r13, q[rbp-24]
     mov r12, q[rbp-16]
     mov r11, q[rbp-8]
 
+    ; TRAP return values: RAX-RDX
+
+    mov ax0, r12
+    mov ax1, $rax
+    mov ax2, rax
+    call RFS.StoreReg
+    mov ax1, $rdx
+    mov ax2, rdx
+    call RFS.StoreReg
+
     mov ax0, r11
     call IDT.DoneHandling
     iret
diff --git a/ka/sys/intr/trap0.k b/ka/sys/intr/trap0.k
index 6ef08da..74835d1 100644
--- a/ka/sys/intr/trap0.k
+++ b/ka/sys/intr/trap0.k
@@ -6,16 +6,19 @@ TRAP0_STACK := 0x300000
 trap0_handler:
 
 .init:
-    mov rax, .impl
+    mov rcx, .impl
     mov rbp, TRAP0_STACK
     jmp TrapHandlers.prolog
 
 .impl:
     mov ax0, r12
+    mov ax1, $rax
+    call RFS.LoadReg
     call RFS.LoadArgs
 
-    b.z ax0, Sys.HLT, .handle_HLT
-    b.z ax0, Sys.DIR, .handle_DIR
+    b.z rax, Sys.HLT, .handle_HLT
+    b.z rax, Sys.FindNext, .handle_FindNext
+    b.z rax, Sys.FindFirst, .handle_FindFirst
 
 .fini:
     jmp TrapHandlers.epilog
@@ -24,8 +27,12 @@ trap0_handler:
 ; Syscall implementations
 ;
 
-.handle_DIR:
-    call CMD.builtins.dir
+.handle_FindFirst:
+    call DISK.FindFirst
+    jmp .fini
+
+.handle_FindNext:
+    call DISK.FindNext
     jmp .fini
 
 .handle_HLT:
diff --git a/ka/usr/cmd/dir.k b/ka/usr/cmd/dir.k
index 543a61d..9e0931a 100644
--- a/ka/usr/cmd/dir.k
+++ b/ka/usr/cmd/dir.k
@@ -12,15 +12,18 @@ CMD.builtins.dir:
 .dirmsg = "Directory of C:\\\n\n"
 
 .first:
+    mov rax, Sys.FindFirst
     mov ax0, .buf
     mov ax1, NAME_MAX
-    call DISK.FindFirst
+    trap 0
+
     jmp .list
 
 .next:
+    mov rax, Sys.FindNext
     mov ax0, .buf
     mov ax1, NAME_MAX
-    call DISK.FindNext
+    trap 0
 
 .list:
     b.z rax, 0, .end