In some operating systems, the null device is a device file that ignores anything written to it but returns that the write worked. This device is called codice_1 on Unix and Unix-like systems, codice_2 or codice_3 on CP/M and DOS (internally codice_4), codice_5 on newer Windows systems (internally codice_6 on Windows NT), codice_7 on Amiga systems, and codice_8 on OpenVMS. In Windows Powershell, the equivalent is codice_9. It returns nothing to any process that reads from it, returning EOF immediately. In IBM DOS/360, OS/360 (MFT, MVT), OS/390 and z/OS operating systems, such files would be assigned in JCL to codice_10.