Newsgroups: comp.sys.ibm.pc.programmer
Path: utzoo!utgpu!watserv1!maytag!watstat!dmurdoch
From: dmurdoch@watstat.uwaterloo.ca (Duncan Murdoch)
Subject: Re: Current directory from batch file
Message-ID: <1990May8.035820.752@maytag.waterloo.edu>
Sender: daemon@maytag.waterloo.edu (Admin)
Organization: University of Waterloo
References: <90122.175401MCCABE@MTUS5.BITNET> <10153.26405d35@vax1.cc.lehigh.edu> <1873@gannet.cl.cam.ac.uk> <90May7.072047edt.19230@me.utoronto.ca> <1990May8.003238.6922@agate.berkeley.edu> <90May7.215707edt.19841@me.utoronto.ca>
Date: Tue, 8 May 90 03:58:20 GMT
Lines: 38

In article <90May7.215707edt.19841@me.utoronto.ca> sun@me.utoronto.ca (Andy Sun Anu-guest) writes:
>
>You've told half of the story, but what about the other half? I am
>interested in how you create that \usr\lib\cdspace file. I don't know
>of any smart way to get this done except by a line of C code:
>
>	main() {printf("cd ");}


It's occasionally handy (as here) to be able to echo text without appending
a CR/LF, so a few years ago I wrote a tiny 23 byte assembler program to do it.
The .DOC file is attached below.

Duncan Murdoch

-----------------------------

EchoN - Echo command line without going to a new line.
  by D.J. Murdoch, 13 Nov 1987
 
This handy little program works like ECHO, but doesn't do a new line at the end.  
I use it in batch files to save a directory: 
 ECHON cd >\olddir.bat 
 CD      >>\olddir.bat
This puts the "cd " into the file olddir.bat in the root directory, then lists 
the current directory into that file on the same line.  Executing OLDDIR any 
time after that puts you back into the original directory.  Unlike PUSHDIR and 
POPDIR, this lasts after you reboot your computer.
 
Here's source code, that could be assembled using DEBUG if ECHON.COM is missing: 
MOV     CL,[0080]    ; Put line length into CL
SUB     CX,+01       ; Subtract 1 to get rid of initial blank
JL      0115         ; Quit if there were no characters
MOV     BX,0001      ; Output to Standard Output...
MOV     DX,0082      ; from command line, starting at the 2nd char...
MOV     AH,40        ; using the write service...
INT     21           ; do it!
INT     20           ; quit