Graeme Geldenhuys wrote:
Hi,
[rant]
I'm just sick of the idiocy of Linux/Unix with there case sensitive
file systems! Google'ing a round for the reason for this, it seems
that in the 60's, it was C programmers that decided that searching for
case sensitive files was easier to implement (and marginally faster).
I find that rather difficult to believe, since C was barely conceived in
the '60s, and back in those days the dominant character I/O devices were
(EBCDIC) punched cards and the (ASCII) ASR-33- both of which IIRC were
de-facto uppercase-only.
Now it might be that by the time the Bell workers were hacking UNIX and
C that they'd got video terminals with full character sets, and it might
be that they gravitated towards lower-case because of received wisdom
that the increased variation between letters makes them easier to read.
But in any event their reluctance to assume any particular mapping
between upper- and lower-case was probably influenced by the fact that
there were still two major character sets (EBCDIC and ASCII) as well as
several minor ones some of which were being used by the US government
(e.g. Fieldata). As discussed in the context of an IBM mainframe port of
FPC, it's bad enough having to deal with multiple mappings in the system
library without having to define them as part of the language.
In any event, history has shown that they probably made the right
decision, and similarly made the right decision when they pegged UNIX
timestamps to GMT/UTC. The fact that Microsoft made different choices
has caused nothing but grief.
All of which suggests that at the current time, when increasing numbers
of people are wrestling with Unicode, we should all be very much aware
of the possible problems that converting (or not) between similar
characters can cause. For example, I found myself writing this yesterday:
$50: { p P } inject:= #$002A; { * }
$DB: { [ } inject:= #$2190; { ← }
$DD: { ] } inject:= #$2192; { → }
Some founts (e.g. the one used by default by GTK2 Lazarus) use almost
identical glyphs for the braces in those comments, and it's only a
matter of time before somebody with more ingenuity than common sense
tries to use these to slip backdoor code past the casual reviewer.
So in summary, (not) translating characters is something that shouldn't
be approached without deep understanding of the issues.
Anybody know of other Linux file systems that have a case insensitive
option? I really thought ext2 had this, but searching now through the
man pages, it seems I was mistaken. Anybody know if Btrfs would have
such an option?
The obvious ones are Windows and possibly CD filesystems mounted with
appropriate options:
# Additional devices.
/dev/fd0 /mnt/floppy vfat noauto,user,shortname=winnt 0 0
/dev/hda4 /mnt/zip vfat noauto,user,shortname=winnt 0 0
/dev/cdrom /mnt/cdrom iso9660 noauto,user,ro 0 0
This obviously includes USB mass storage devices such as cameras.
Not sure about btrfs. I tried using it a few months ago but it was very
unclear whether I was getting any useful compression when it was
enabled, I subsequently discovered that that depends on kernel version-
frankly, it's too near the "bleeding edge" to be used in anger.
--
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk
[Opinions above are the author's, not those of his employers or colleagues]
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
