Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!olivea!samsung!think.com!cass.ma02.bull.com!mips2!bull.bull.fr!corton!mcsun!sunic!ugle.unit.no!solan1.solan.unit.no!stoeen From: stoeen@solan.unit.no (Asbj|rn St|en) Newsgroups: comp.os.msdos.misc Subject: Re: Why is erase *.* slower with 4dos.com than with command.com? Message-ID: <1991May20.143302.26689@ugle.unit.no> Date: 20 May 91 14:33:02 GMT References: <1991May20.064529.1764@nic.funet.fi> Sender: news@ugle.unit.no Reply-To: stoeen@solan.unit.no (Asbj|rn St|en) Organization: Norwegian Institute of Technology Lines: 32 In article <1991May20.064529.1764@nic.funet.fi>, akoivuma@finsun.csc.fi (Antti Koivumaki) writes: |> I have noticed that when I use 4dos.com, erase *.* works much slower than |> when command.com is used. I tested this by erasing 100 files using each. |> I did this on an otherwise empty hard disk partition. The result: |> - using 4dos.com (v. 4.02), erase/q *.* takes about 5 seconds |> - using command.com (of DOS 3.3), erase *.* takes less than 0.5 seconds. |> |> A bug or a feature? Any explanations? Perhaps this is the explanation: COMMAND.COM uses FCB (file control block) commands when it erases files. This erase command can handle wildcards such as '*'. 4DOS.COM uses the ASCIIZ erase command, which does not handle wildcards. This means that 4dos has to find each file, then erase them one by one. Why does 4dos use the slower version? By using ASCIIZ commands it is easier to implement a 'prompt' facility for each file. Besides, the ASCIIZ erase command can take a complete path specification, while the FCB function only works on the current directory. This means that the file specification has to be parsed, the current directory has to be changed, erase files, then switch back to the previous directory. The FCB function is much more tedious. Hope this was clear enough... -- _ Asbjoern Stoeen / \ /___ Studpost 188 /___\ // 7034 Trondheim-NTH / \ / \__ Norway / \ (stoeen@solan.unit.no) / ___/