bin/41526: re-support /usr/bin/vi's -F option

[Ephaeton%gmx.net@localhost]

>Number:         41526
>Category:       bin
>Synopsis:       re-support /usr/bin/vi's -F option
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Tue Jun 02 17:00:00 +0000 2009
>Originator:     Martin S. Weber
>Release:        NetBSD 5.0_STABLE
>Organization:
        
>Environment:
        
        
System: NetBSD agamemnon.entropie.local 5.0_STABLE NetBSD 5.0_STABLE 
(AGAMEMNON5) #0: Fri May 22 19:03:57 EDT 2009 
root%agamemnon.entropie.local@localhost:/home/netbsd/obj/sys/arch/i386/compile/AGAMEMNON5
 i386
Architecture: i386
Machine: i386
>Description:
        /usr/bin/vi used to have the "-F" option which would prevent reading in
        the whole file at once. This used to be very, very useful when looking
        at really big files. It worked responsive (because it did not try to 
read
        the whole file), and it worked no matter the size of your /var/tmp.
        To quote a previous co-worker of mine who often had to look at really
        big files: "I usually use nedit but this is one of the use-cases where
        I love vi". I whole-heartedly agree with him.
        With the update of nvi, the -F option got thrown away 
        ("vi: -F option no longer supported"). This inverts the situation where
        vi once won over nedit: The whole file needs to be read in, which can
        take a considerable amount of time; also the vi backup routine tries to
        make a copy of the file to /var/tmp/vi.recover. Aside of the obvious 
        problem that vi no takes quite an amount of time to open big files, 
this 
        limits vi's usefulness on big files: the size of the /var partition 
        now limits the size of files one can open. In my opinion this is a 
serious
        regression of vi's features.
>How-To-Repeat:
        try to open a file bigger than your /var partition.
        
>Fix:
        - don't use multiple partitions
         -> but then vi without -F still is slow and wasteful
        - re-support -F
        

>Unformatted: