[NTLUG:Discuss] UMSDOS vs lin4win

[Mike]

UMSDOS vs Lin4Win

UMSDOS defines individual msdos files for each file in the 
linux session. This allows unrestricted (root) access to 
every linux file while you are in windows. that is... every 
single file can be manipulated while you are logged into 
windows, and changing any of a number of files can cause 
the linux session to fail to start properly. For example, 
opening a unix script in windows notepad (under windows, 
not wine) then saving back to the same location could cause 
unix lined feed (CR/LF) characters to be replaced by a dos 
return (^M) character thereby totally messing up the 
script. Depending on the file, this can cause you to end up 
not successfully starting the unix session, and never being 
able to 'see' a problem with your script that linux is 
complaining about. The upside is that free space is 
available to either linux or windows. The downside is 
nothing that should be root access is protected from a 
windows user. 

Lin4Win packages the whole linux filesystem into one big 
windows image file, effectively preventing you from doing 
something to destabalize your linux system by mistake as 
described above. There are tools to open image files from 
within windows, but you know your working on the linux 
image at that point and  are far less likely to pull 
something as stupid as trying to edit a unix shell in 
notepad. The downside is that the linux grabs drive space 
for the whole linux filesystem---free space and all, so you 
have less file space availabe in each login.  another 
downside to lin4win is it uses a virtual memory swap file 
instead of a swap partition.  This results in all virtual 
page routines running at 1/2 the speed or slower that a 
real swap partition would.   the upside vs. umsdos systems 
is that the filesystem is somewhat protected from changes 
while the linux kernal is not active.