diff --git a/diskpart/lib/diskpart.lua b/diskpart/lib/diskpart.lua
index 9f1b9bf..c7c2d88 100644
--- a/diskpart/lib/diskpart.lua
+++ b/diskpart/lib/diskpart.lua
@@ -1,3 +1,4 @@
+local component = require "component"
 local partition = {}
 
 local eformat = "c20c4>I4>I4"
diff --git a/fdisk/exec/fdisk.lua b/fdisk/exec/fdisk.lua
index 4189026..e142887 100644
--- a/fdisk/exec/fdisk.lua
+++ b/fdisk/exec/fdisk.lua
@@ -1,3 +1,4 @@
+local component = require "component"
 local tA = {...}
 local fdisk = {}
 local addr = component.get(table.remove(tA, 1))
@@ -15,15 +16,18 @@ function fdisk.show()
 end
 function fdisk.del(i)
  local pt = require("diskpart").getPartitions(addr)
- table.remove(pt, i)
+ table.remove(pt, tonumber(i))
+ require("diskpart").setPartitions(addr, pt)
+ fdisk.show()
+end
+function fdisk.set(id, name, ftype, start, len)
+ local pt = require("diskpart").getPartitions(addr)
+ pt[tonumber(id)] = {name, ftype, tonumber(start), tonumber(len)}
  require("diskpart").setPartitions(addr, pt)
  fdisk.show()
 end
 function fdisk.add(name, ftype, start, len)
- local pt = require("diskpart").getPartitions(addr)
- pt[#pt+1] = {name, ftype, start, len}
- require("diskpart").setPartitions(addr, pt)
- fdisk.show()
+ fdisk.set(#require("diskpart").getPartitions(addr)+1, name, ftype, start, len)
 end
 
 assert(fdisk[cmd], "unknown command")