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Groups > comp.lang.c > #172150 > unrolled thread

Piping to stdin

Started byMalcolm McLean <malcolm.arthur.mclean@gmail.com>
First post2023-08-13 06:42 -0700
Last post2023-08-14 21:14 +0000
Articles 20 on this page of 102 — 27 participants

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  Piping to stdin Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-08-13 06:42 -0700
    Re: Piping to stdin Spiros Bousbouras <spibou@gmail.com> - 2023-08-13 13:55 +0000
      Re: Piping to stdin Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-08-13 07:07 -0700
        Re: Piping to stdin Bart <bc@freeuk.com> - 2023-08-13 15:21 +0100
          Re: Piping to stdin Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-08-13 07:31 -0700
            Re: Piping to stdin Bart <bc@freeuk.com> - 2023-08-13 16:40 +0100
          Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-13 16:08 +0000
        Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-13 16:07 +0000
        Re: Piping to stdin Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-08-13 17:26 +0000
          Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-13 19:09 +0000
            Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-13 20:45 +0000
        Re: Piping to stdin Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-08-13 20:53 +0100
          Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-13 20:47 +0000
        Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-14 00:59 +0000
          Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-14 03:07 +0000
            Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-14 03:12 +0000
              Re: Piping to stdin kalevi@kolttonen.fi (Kalevi Kolttonen) - 2023-08-14 15:14 +0000
                Re: Piping to stdin "Gary R. Schmidt" <grschmidt@acm.org> - 2023-08-15 12:50 +1000
                  Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-15 04:59 +0000
                    Re: Piping to stdin Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-14 23:15 -0700
                    Re: Piping to stdin Richard Kettlewell <invalid@invalid.invalid> - 2023-08-15 08:50 +0100
                      Dealing with weird filenames (Was: Piping to stdin) gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-15 08:10 +0000
                      Re: Piping to stdin David Brown <david.brown@hesbynett.no> - 2023-08-15 15:34 +0200
                        Re: Piping to stdin Richard Harnden <richard.nospam@gmail.com> - 2023-08-15 19:50 +0100
                          Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-15 20:16 +0000
                          Re: Piping to stdin vallor <vallor@cultnix.org> - 2023-08-16 06:34 +0000
                        Re: Piping to stdin Richard Kettlewell <invalid@invalid.invalid> - 2023-08-16 17:39 +0100
                          Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-16 17:37 +0000
                            Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-16 17:43 +0000
                            Re: Piping to stdin Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-16 13:35 -0700
                            Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-17 14:51 +0300
                      Re: Piping to stdin James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-08-16 01:37 -0400
                        Re: Piping to stdin David Brown <david.brown@hesbynett.no> - 2023-08-16 13:14 +0200
                    Re: Piping to stdin Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2023-08-15 12:08 -0600
                      Re: Piping to stdin Richard Harnden <richard.nospam@gmail.com> - 2023-08-16 09:32 +0100
                        Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-16 17:27 +0300
                  Re: Piping to stdin kalevi@kolttonen.fi (Kalevi Kolttonen) - 2023-08-15 14:30 +0000
                    Re: Piping to stdin Giovanni <lsodgf0@home.net.it> - 2023-08-15 17:14 +0200
                      Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-15 15:48 +0000
                        Re: Piping to stdin kalevi@kolttonen.fi (Kalevi Kolttonen) - 2023-08-15 16:12 +0000
                          Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-15 16:15 +0000
                            Re: Piping to stdin kalevi@kolttonen.fi (Kalevi Kolttonen) - 2023-08-15 16:22 +0000
                              Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-17 10:26 +0000
                                Re: Piping to stdin kalevi@kolttonen.fi (Kalevi Kolttonen) - 2023-08-17 14:23 +0000
                                  Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-17 15:25 +0000
                            Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-15 17:33 +0000
                            Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-15 23:32 +0300
                              Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-17 10:32 +0000
                                Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-17 14:57 +0300
                                  Re: Piping to stdin Michael S <already5chosen@yahoo.com> - 2023-08-17 05:14 -0700
                                  Wrecking a good thing? (Was: Piping to stdin) gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-17 14:09 +0000
                                    Re: Wrecking a good thing? Phil Carmody <pc+usenet@asdf.org> - 2023-08-18 00:39 +0300
                                    Re: Wrecking a good thing? (Was: Piping to stdin) David Brown <david.brown@hesbynett.no> - 2023-08-18 11:17 +0200
                                  Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-17 15:14 +0000
                                  Re: Piping to stdin Öö Tiib <ootiib@hot.ee> - 2023-08-17 08:58 -0700
                                Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-17 13:52 +0000
                                  Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-17 15:20 +0000
                                  Re: Piping to stdin Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-17 13:43 -0700
                                  Re: Piping to stdin David Brown <david.brown@hesbynett.no> - 2023-08-18 11:28 +0200
                                Re: Piping to stdin Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-08-17 21:52 +0100
                                  Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-19 13:33 +0300
                                    Re: Piping to stdin Oğuz <oguzismailuysal@gmail.com> - 2023-08-19 16:15 +0300
                                      Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-19 14:48 +0000
                                        Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-20 17:24 +0000
                                          Re: Piping to stdin Muttley@dastardlyhq.com - 2023-08-20 19:21 +0000
                                        Re: Piping to stdin Rainer Weikusat <rweikusat@talktalk.net> - 2023-08-20 21:57 +0100
                                          What language is this? (Was: Piping to stdin) gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-20 22:33 +0000
                                            Re: What language is this? (Was: Piping to stdin) scott@slp53.sl.home (Scott Lurndal) - 2023-08-21 01:26 +0000
                                              Re: What language is this? (Was: Piping to stdin) gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-21 02:57 +0000
                                                Re: What language is this? Rainer Weikusat <rweikusat@talktalk.net> - 2023-08-21 17:16 +0100
                                                  Re: What language is this? gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-21 19:10 +0000
                                                    Re: What language is this? Rainer Weikusat <rweikusat@talktalk.net> - 2023-08-21 20:31 +0100
                                                      Re: What language is this? gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-21 20:29 +0000
                                                        Re: What language is this? Rainer Weikusat <rweikusat@talktalk.net> - 2023-08-21 21:48 +0100
                                              Re: What language is this? (Was: Piping to stdin) Muttley@dastardlyhq.com - 2023-08-21 06:50 +0000
                                    Re: Piping to stdin Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-08-19 21:14 +0100
                          Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-15 23:24 +0300
                            Re: Piping to stdin Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-08-15 20:50 +0000
                              Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-16 17:11 +0300
                                Re: Piping to stdin Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2023-08-16 15:25 +0000
                                  Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-16 19:29 +0000
                                  Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-17 14:49 +0300
                          Re: Piping to stdin Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-08-16 03:20 +0100
                    Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-15 18:33 +0300
          Re: Piping to stdin "Nuno Silva" <nunojsilva@invalid.invalid> - 2023-08-14 09:45 +0100
    Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-13 16:06 +0000
      Re: Piping to stdin Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-13 17:09 -0700
        Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-14 01:03 +0000
          Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-14 04:00 +0000
            Re: Piping to stdin Phil Carmody <pc+usenet@asdf.org> - 2023-08-14 12:20 +0300
            Re: Piping to stdin Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-08-14 02:44 -0700
              Re: Piping to stdin Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-08-14 03:54 -0700
                Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-14 11:22 +0000
              Re: Piping to stdin Kaz Kylheku <864-117-4973@kylheku.com> - 2023-08-14 15:49 +0000
                Re: Piping to stdin Ben Bacarisse <ben.usenet@bsb.me.uk> - 2023-08-14 17:19 +0100
          Re: Piping to stdin Jim Jackson <jj@franjam.org.uk> - 2023-08-14 17:21 +0000
            Re: Piping to stdin Michael S <already5chosen@yahoo.com> - 2023-08-15 08:02 -0700
    Re: Piping to stdin John Forkosh <forkosh@panix.com> - 2023-08-14 03:15 +0000
    Re: Piping to stdin gazelle@shell.xmission.com (Kenny McCormack) - 2023-08-14 11:28 +0000
      Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-14 15:41 +0000
        Re: Piping to stdin Richard Harnden <richard.nospam@gmail.com> - 2023-08-14 22:02 +0100
          Re: Piping to stdin scott@slp53.sl.home (Scott Lurndal) - 2023-08-14 21:14 +0000

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#172242

FromRichard Kettlewell <invalid@invalid.invalid>
Date2023-08-15 08:50 +0100
Message-ID<wwvleeceobt.fsf@LkoBDZeT.terraraq.uk>
In reply to#172240
Kaz Kylheku <864-117-4973@kylheku.com> writes:
> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>> Ahah!  You don't have users, do you?
>>
>> No doubt you also don't encounter filenames with spaces in them, or 
>> carriage returns, or other garbage.
>
> The interesction of:
>
> - Users who make filenames like "-foo" and "monthly forecast.xls"
>
> - Users who sit in a POSIX shell expanding wildcards like *
>   in the same directory.
>
> is probababy vanishingly nil, and the subset of those who do the
> above in the same directory is even smaller.

The cases I’ve encountered are where someone accidentally creates a file
with a weird name (starts with - or whatever) and then has trouble
deleting it. I don’t think they got as far as having accidents with
wildcards in the cases I remember, but the basic setup of a file with a
ridiculous name and a non-expert user does happen occasionally.

> Now admin scripts do have to handle the files created by the goofy
> users in the first category.
>
> Admin scripts don't ahve to worry about users creating a file called
> -, because admin scripts won't be run in the directory where the user
> did that. Not even scripts which do process paths traversing that
> directory. The admin (or cron, or systemd or whatever) will run those
> from somewhere else.

The usual example of an ‘admin script’ that has to deal with bizarre
user-created file is a /tmp cleaner. Not quite the same issue as we
started with here but depending on how experienced the script author is
there is plenty of room for accidental or adversarial mischief.

-- 
https://www.greenend.org.uk/rjk/

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#172244 — Dealing with weird filenames (Was: Piping to stdin)

Fromgazelle@shell.xmission.com (Kenny McCormack)
Date2023-08-15 08:10 +0000
SubjectDealing with weird filenames (Was: Piping to stdin)
Message-ID<ubfbu7$3ja4p$1@news.xmission.com>
In reply to#172242
In article <wwvleeceobt.fsf@LkoBDZeT.terraraq.uk>,
Richard Kettlewell  <invalid@invalid.invalid> wrote:
...
>The cases I've encountered are where someone accidentally creates a file
>with a weird name (starts with - or whatever) and then has trouble
>deleting it. I don't think they got as far as having accidents with
>wildcards in the cases I remember, but the basic setup of a file with a
>ridiculous name and a non-expert user does happen occasionally.

This is a situation where using a GUI file manager (Windows Explorer
equivalent - whatever they are calling it in Unix/Linux these days).
Weirdly named files are no problem to delete from a GUI, since no shell is
involved.

-- 
If Jeb is  Charlie Brown kicking a football-pulled-away, Mitt  is a '50s
housewife with a  black eye who insists to her  friends the roast wasn't
dry.

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#172276

FromDavid Brown <david.brown@hesbynett.no>
Date2023-08-15 15:34 +0200
Message-ID<ubfus8$2rc7s$1@dont-email.me>
In reply to#172242
On 15/08/2023 09:50, Richard Kettlewell wrote:
> Kaz Kylheku <864-117-4973@kylheku.com> writes:
>> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>>> Ahah!  You don't have users, do you?
>>>
>>> No doubt you also don't encounter filenames with spaces in them, or
>>> carriage returns, or other garbage.
>>
>> The interesction of:
>>
>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>
>> - Users who sit in a POSIX shell expanding wildcards like *
>>    in the same directory.
>>
>> is probababy vanishingly nil, and the subset of those who do the
>> above in the same directory is even smaller.
> 
> The cases I’ve encountered are where someone accidentally creates a file
> with a weird name (starts with - or whatever) and then has trouble
> deleting it. I don’t think they got as far as having accidents with
> wildcards in the cases I remember, but the basic setup of a file with a
> ridiculous name and a non-expert user does happen occasionally.
> 

It's usually sufficient just to put the awkward name inside quotation marks.

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#172321

FromRichard Harnden <richard.nospam@gmail.com>
Date2023-08-15 19:50 +0100
Message-ID<ubghe4$2ubhu$1@dont-email.me>
In reply to#172276
On 15/08/2023 14:34, David Brown wrote:
> On 15/08/2023 09:50, Richard Kettlewell wrote:
>> Kaz Kylheku <864-117-4973@kylheku.com> writes:
>>> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>>>> Ahah!  You don't have users, do you?
>>>>
>>>> No doubt you also don't encounter filenames with spaces in them, or
>>>> carriage returns, or other garbage.
>>>
>>> The interesction of:
>>>
>>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>>
>>> - Users who sit in a POSIX shell expanding wildcards like *
>>>    in the same directory.
>>>
>>> is probababy vanishingly nil, and the subset of those who do the
>>> above in the same directory is even smaller.
>>
>> The cases I’ve encountered are where someone accidentally creates a file
>> with a weird name (starts with - or whatever) and then has trouble
>> deleting it. I don’t think they got as far as having accidents with
>> wildcards in the cases I remember, but the basic setup of a file with a
>> ridiculous name and a non-expert user does happen occasionally.
>>
> 
> It's usually sufficient just to put the awkward name inside quotation 
> marks.
> 
> 

But people won't/don't do that.

Also:

$ >-f
$ >-r
$ rm *

How to safely cater for all 'weird' inputs?




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#172329

Fromscott@slp53.sl.home (Scott Lurndal)
Date2023-08-15 20:16 +0000
Message-ID<o2RCM.110346$PlBb.53343@fx42.iad>
In reply to#172321
Richard Harnden <richard.nospam@gmail.com> writes:
>On 15/08/2023 14:34, David Brown wrote:
>> On 15/08/2023 09:50, Richard Kettlewell wrote:
>>> Kaz Kylheku <864-117-4973@kylheku.com> writes:
>>>> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>>>>> Ahah!  You don't have users, do you?
>>>>>
>>>>> No doubt you also don't encounter filenames with spaces in them, or
>>>>> carriage returns, or other garbage.
>>>>
>>>> The interesction of:
>>>>
>>>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>>>
>>>> - Users who sit in a POSIX shell expanding wildcards like *
>>>>    in the same directory.
>>>>
>>>> is probababy vanishingly nil, and the subset of those who do the
>>>> above in the same directory is even smaller.
>>>
>>> The cases I’ve encountered are where someone accidentally creates a file
>>> with a weird name (starts with - or whatever) and then has trouble
>>> deleting it. I don’t think they got as far as having accidents with
>>> wildcards in the cases I remember, but the basic setup of a file with a
>>> ridiculous name and a non-expert user does happen occasionally.
>>>
>> 
>> It's usually sufficient just to put the awkward name inside quotation 
>> marks.
>> 
>> 
>
>But people won't/don't do that.
>
>Also:
>
>$ >-f
>$ >-r
>$ rm *
>
>How to safely cater for all 'weird' inputs?

Well, like any tool, it can be misused.  I don't blame
the tool for that, when the tool is still useful.

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#172351

Fromvallor <vallor@cultnix.org>
Date2023-08-16 06:34 +0000
Message-ID<ubhqlo$374bv$1@dont-email.me>
In reply to#172321
On Tue, 15 Aug 2023 19:50:44 +0100, Richard Harnden
<richard.nospam@gmail.com> wrote in <ubghe4$2ubhu$1@dont-email.me>:

> On 15/08/2023 14:34, David Brown wrote:
>> On 15/08/2023 09:50, Richard Kettlewell wrote:
>>> Kaz Kylheku <864-117-4973@kylheku.com> writes:
>>>> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>>>>> Ahah!  You don't have users, do you?
>>>>>
>>>>> No doubt you also don't encounter filenames with spaces in them, or
>>>>> carriage returns, or other garbage.
>>>>
>>>> The interesction of:
>>>>
>>>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>>>
>>>> - Users who sit in a POSIX shell expanding wildcards like *
>>>>    in the same directory.
>>>>
>>>> is probababy vanishingly nil, and the subset of those who do the
>>>> above in the same directory is even smaller.
>>>
>>> The cases I’ve encountered are where someone accidentally creates a
>>> file with a weird name (starts with - or whatever) and then has
>>> trouble deleting it. I don’t think they got as far as having accidents
>>> with wildcards in the cases I remember, but the basic setup of a file
>>> with a ridiculous name and a non-expert user does happen occasionally.
>>>
>>>
>> It's usually sufficient just to put the awkward name inside quotation
>> marks.
>> 
>> 
>> 
> But people won't/don't do that.
> 
> Also:
> 
> $ >-f $ >-r $ rm *
> 
> How to safely cater for all 'weird' inputs?

(wondering if this belongs in comp.unix.shell, but here goes:)

In the 90's and maybe the early 2000's, many of our
(large installation) servers had a '-i' file in their
root directories.  I'm not sure how widespread the
practice was, but I don't think we invented it.

-- 
-v

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#172387

FromRichard Kettlewell <invalid@invalid.invalid>
Date2023-08-16 17:39 +0100
Message-ID<wwvr0o3j618.fsf@LkoBDZeT.terraraq.uk>
In reply to#172276
David Brown <david.brown@hesbynett.no> writes:
> On 15/08/2023 09:50, Richard Kettlewell wrote:
>> The cases I’ve encountered are where someone accidentally creates a
>> file with a weird name (starts with - or whatever) and then has
>> trouble deleting it. I don’t think they got as far as having
>> accidents with wildcards in the cases I remember, but the basic setup
>> of a file with a ridiculous name and a non-expert user does happen
>> occasionally.
>
> It's usually sufficient just to put the awkward name inside quotation marks.

In the case we started with, quoting is not sufficient.

-- 
https://www.greenend.org.uk/rjk/

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#172397

Fromscott@slp53.sl.home (Scott Lurndal)
Date2023-08-16 17:37 +0000
Message-ID<TP7DM.428701$U3w1.87269@fx09.iad>
In reply to#172387
Richard Kettlewell <invalid@invalid.invalid> writes:
>David Brown <david.brown@hesbynett.no> writes:
>> On 15/08/2023 09:50, Richard Kettlewell wrote:
>>> The cases I’ve encountered are where someone accidentally creates a
>>> file with a weird name (starts with - or whatever) and then has
>>> trouble deleting it. I don’t think they got as far as having
>>> accidents with wildcards in the cases I remember, but the basic setup
>>> of a file with a ridiculous name and a non-expert user does happen
>>> occasionally.
>>
>> It's usually sufficient just to put the awkward name inside quotation marks.
>
>In the case we started with, quoting is not sufficient.

Doesn't that depend on the type of quote?   glob characters (*, ?) are
treated as regular characters in single quotes, for example.

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#172398

Fromgazelle@shell.xmission.com (Kenny McCormack)
Date2023-08-16 17:43 +0000
Message-ID<ubj1rr$3l8k0$1@news.xmission.com>
In reply to#172397
In article <TP7DM.428701$U3w1.87269@fx09.iad>,
Scott Lurndal <slp53@pacbell.net> wrote:
>Richard Kettlewell <invalid@invalid.invalid> writes:
>>David Brown <david.brown@hesbynett.no> writes:
>>> On 15/08/2023 09:50, Richard Kettlewell wrote:
>>>> The cases Ive encountered are where someone accidentally creates a
>>>> file with a weird name (starts with - or whatever) and then has
>>>> trouble deleting it. I dont think they got as far as having
>>>> accidents with wildcards in the cases I remember, but the basic setup
>>>> of a file with a ridiculous name and a non-expert user does happen
>>>> occasionally.
>>>
>>> It's usually sufficient just to put the awkward name inside
>>> quotation marks.
>>
>>In the case we started with, quoting is not sufficient.
>
>Doesn't that depend on the type of quote?   glob characters (*, ?) are
>treated as regular characters in single quotes, for example.

You're missing the point.

-- 
Treating the stock market indexes as general measures of the well-being of a
society is like treating your blood pressure as an indicator of health.  The
higher, the better, right?  In fact, a high stock market is good for the investor
class, but it means the rest of us are getting screwed better than ever.

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#172409

FromKeith Thompson <Keith.S.Thompson+u@gmail.com>
Date2023-08-16 13:35 -0700
Message-ID<877cpulo80.fsf@nosuchdomain.example.com>
In reply to#172397
scott@slp53.sl.home (Scott Lurndal) writes:
> Richard Kettlewell <invalid@invalid.invalid> writes:
>>David Brown <david.brown@hesbynett.no> writes:
>>> On 15/08/2023 09:50, Richard Kettlewell wrote:
>>>> The cases I’ve encountered are where someone accidentally creates a
>>>> file with a weird name (starts with - or whatever) and then has
>>>> trouble deleting it. I don’t think they got as far as having
>>>> accidents with wildcards in the cases I remember, but the basic setup
>>>> of a file with a ridiculous name and a non-expert user does happen
>>>> occasionally.
>>>
>>> It's usually sufficient just to put the awkward name inside quotation marks.
>>
>>In the case we started with, quoting is not sufficient.
>
> Doesn't that depend on the type of quote?   glob characters (*, ?) are
> treated as regular characters in single quotes, for example.

Not in this case -- and glob characters are not expanded in either
single or doublle quotes.

The difference is that * and ? are expanded by the shell, so the
invoked command never sees them, but arguments starting with -
are treated specially by the command itself.

If you have a file named *, you can delete it with `rm '*'` or
`rm "*"`, or `rm \*`.

If you have a file named -r, you can delete it with `rm ./-r`, or
`rm -- -r` if your rm implementation supports that (POSIX doesn't
specify it).

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */

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#172447

FromPhil Carmody <pc+usenet@asdf.org>
Date2023-08-17 14:51 +0300
Message-ID<87y1i9zy1s.fsf@fatphil.org>
In reply to#172397
scott@slp53.sl.home (Scott Lurndal) writes:
> Richard Kettlewell <invalid@invalid.invalid> writes:
>>David Brown <david.brown@hesbynett.no> writes:
>>> On 15/08/2023 09:50, Richard Kettlewell wrote:
>>>> The cases I’ve encountered are where someone accidentally creates a
>>>> file with a weird name (starts with - or whatever) and then has
>>>> trouble deleting it. I don’t think they got as far as having
>>>> accidents with wildcards in the cases I remember, but the basic setup
>>>> of a file with a ridiculous name and a non-expert user does happen
>>>> occasionally.
>>>
>>> It's usually sufficient just to put the awkward name inside quotation marks.
>>
>>In the case we started with, quoting is not sufficient.
>
> Doesn't that depend on the type of quote?   glob characters (*, ?) are
> treated as regular characters in single quotes, for example.

No, it depends on the program you intend to pass the filename to, and
how it treats its arguments.

Which we don't know. So we can't say anything more at the moment.

Phil
-- 
We are no longer hunters and nomads. No longer awed and frightened, as we have
gained some understanding of the world in which we live. As such, we can cast
aside childish remnants from the dawn of our civilization.
-- NotSanguine on SoylentNews, after Eugen Weber in /The Western Tradition/

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#172350

FromJames Kuyper <jameskuyper@alumni.caltech.edu>
Date2023-08-16 01:37 -0400
Message-ID<ubhnad$36om0$1@dont-email.me>
In reply to#172242
On 8/15/23 03:50, Richard Kettlewell wrote:
> Kaz Kylheku <864-117-4973@kylheku.com> writes:
...
>> The interesction of:
>>
>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>
>> - Users who sit in a POSIX shell expanding wildcards like *
>>   in the same directory.
>>
>> is probababy vanishingly nil, and the subset of those who do the
>> above in the same directory is even smaller.
> 
> The cases I’ve encountered are where someone accidentally creates a file
> with a weird name (starts with - or whatever) and then has trouble
> deleting it. I don’t think they got as far as having accidents with
> wildcards in the cases I remember, but the basic setup of a file with a
> ridiculous name and a non-expert user does happen occasionally.

The most bizarre filenames I've seen were generally created by one of
two mechanisms: Copy-and-pasting a command line into a terminal window,
where a minor slip of the mouse resulted in the copy including far more
material than it was supposed to. Most of the resulting lines of text do
nothing, but every once in a while a line starts with a word that is a
valid unix command name, and some very weird things happen.

The second scenario is where someone stupidly gave an ordinary text file
execute permission, and someone else accidentally typed the name of that
file in a context where it would invoke the supposed "executable". The
results were similar to those from the copy-and-past problem, except
that some of the text files were much longer, increasing the chance of a
line from the file actually resulting in non-trivial behavior.

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#172366

FromDavid Brown <david.brown@hesbynett.no>
Date2023-08-16 13:14 +0200
Message-ID<ubib2o$394g8$5@dont-email.me>
In reply to#172350
On 16/08/2023 07:37, James Kuyper wrote:
> On 8/15/23 03:50, Richard Kettlewell wrote:
>> Kaz Kylheku <864-117-4973@kylheku.com> writes:
> ...
>>> The interesction of:
>>>
>>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>>
>>> - Users who sit in a POSIX shell expanding wildcards like *
>>>    in the same directory.
>>>
>>> is probababy vanishingly nil, and the subset of those who do the
>>> above in the same directory is even smaller.
>>
>> The cases I’ve encountered are where someone accidentally creates a file
>> with a weird name (starts with - or whatever) and then has trouble
>> deleting it. I don’t think they got as far as having accidents with
>> wildcards in the cases I remember, but the basic setup of a file with a
>> ridiculous name and a non-expert user does happen occasionally.
> 
> The most bizarre filenames I've seen were generally created by one of
> two mechanisms: Copy-and-pasting a command line into a terminal window,
> where a minor slip of the mouse resulted in the copy including far more
> material than it was supposed to. Most of the resulting lines of text do
> nothing, but every once in a while a line starts with a word that is a
> valid unix command name, and some very weird things happen.
> 
> The second scenario is where someone stupidly gave an ordinary text file
> execute permission, and someone else accidentally typed the name of that
> file in a context where it would invoke the supposed "executable". The
> results were similar to those from the copy-and-past problem, except
> that some of the text files were much longer, increasing the chance of a
> line from the file actually resulting in non-trivial behavior.

I have seen some odd names on file servers, when people have tried to 
make certain files sort at the top or bottom of a list by prefixing with 
odd characters (such as a space - that's always fun).

Many punctuation marks that are easy to use in gui programs are awkward 
on the command line - brackets, quotation marks, ampersand, etc.  Mostly 
you can handle them on the command line by using quotation marks, or 
backslash escapes.

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#172320

FromJoe Pfeiffer <pfeiffer@cs.nmsu.edu>
Date2023-08-15 12:08 -0600
Message-ID<1by1ic2n67.fsf@pfeifferfamily.net>
In reply to#172240
Kaz Kylheku <864-117-4973@kylheku.com> writes:

> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>> On 15/08/2023 01:14, Kalevi Kolttonen wrote:
>>> In comp.unix.programmer Kenny McCormack <gazelle@shell.xmission.com> wrote:
>>>> You know that - and I know that - but do they know that?
>>> 
>>> It makes no difference. In the real world nobody has
>>> files named '-'.
>>> 
>>> br,
>>> KK
>>
>> Ahah!  You don't have users, do you?
>>
>> No doubt you also don't encounter filenames with spaces in them, or 
>> carriage returns, or other garbage.
>
> The interesction of:
>
> - Users who make filenames like "-foo" and "monthly forecast.xls"
>
> - Users who sit in a POSIX shell expanding wildcards like *
>   in the same directory.
>
> is probababy vanishingly nil, and the subset of those who do the
> above in the same directory is even smaller.
>
> Now admin scripts do have to handle the files created by the goofy users
> in the first category.
>
> Admin scripts don't ahve to worry about users creating a file
> called -, because admin scripts won't be run in the directory
> where the user did that. Not even scripts which do process
> paths traversing that directory. The admin (or cron, or systemd or
> whatever) will run those from somewhere else.

Though I expect just about everyone has tried to run foo -xyz and
inadvertently run foo - xyz instead, ending up with a file named - and
one named xyz.

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#172355

FromRichard Harnden <richard.nospam@gmail.com>
Date2023-08-16 09:32 +0100
Message-ID<ubi1ij$37upp$1@dont-email.me>
In reply to#172320
On 15/08/2023 19:08, Joe Pfeiffer wrote:
> Kaz Kylheku <864-117-4973@kylheku.com> writes:
> 
>> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>>> On 15/08/2023 01:14, Kalevi Kolttonen wrote:
>>>> In comp.unix.programmer Kenny McCormack <gazelle@shell.xmission.com> wrote:
>>>>> You know that - and I know that - but do they know that?
>>>>
>>>> It makes no difference. In the real world nobody has
>>>> files named '-'.
>>>>
>>>> br,
>>>> KK
>>>
>>> Ahah!  You don't have users, do you?
>>>
>>> No doubt you also don't encounter filenames with spaces in them, or
>>> carriage returns, or other garbage.
>>
>> The interesction of:
>>
>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>
>> - Users who sit in a POSIX shell expanding wildcards like *
>>    in the same directory.
>>
>> is probababy vanishingly nil, and the subset of those who do the
>> above in the same directory is even smaller.
>>
>> Now admin scripts do have to handle the files created by the goofy users
>> in the first category.
>>
>> Admin scripts don't ahve to worry about users creating a file
>> called -, because admin scripts won't be run in the directory
>> where the user did that. Not even scripts which do process
>> paths traversing that directory. The admin (or cron, or systemd or
>> whatever) will run those from somewhere else.
> 
> Though I expect just about everyone has tried to run foo -xyz and
> inadvertently run foo - xyz instead, ending up with a file named - and
> one named xyz.


$ rm -rf * .tmp
rm: .tmp: No such file or directory
$ unrm
-ksh: unrm: not found
$ man cpio

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#172381

FromPhil Carmody <pc+usenet@asdf.org>
Date2023-08-16 17:27 +0300
Message-ID<878rab2hbb.fsf@fatphil.org>
In reply to#172355
Richard Harnden <richard.nospam@gmail.com> writes:
> On 15/08/2023 19:08, Joe Pfeiffer wrote:
>> Kaz Kylheku <864-117-4973@kylheku.com> writes:
>>> On 2023-08-15, Gary R. Schmidt <grschmidt@acm.org> wrote:
>>>> On 15/08/2023 01:14, Kalevi Kolttonen wrote:
>>>>> In comp.unix.programmer Kenny McCormack <gazelle@shell.xmission.com> wrote:
>>>>>> You know that - and I know that - but do they know that?
>>>>>
>>>>> It makes no difference. In the real world nobody has
>>>>> files named '-'.
>>>>>
>>>>> br,
>>>>> KK
>>>>
>>>> Ahah!  You don't have users, do you?
>>>>
>>>> No doubt you also don't encounter filenames with spaces in them, or
>>>> carriage returns, or other garbage.
>>>
>>> The interesction of:
>>>
>>> - Users who make filenames like "-foo" and "monthly forecast.xls"
>>>
>>> - Users who sit in a POSIX shell expanding wildcards like *
>>>    in the same directory.
>>>
>>> is probababy vanishingly nil, and the subset of those who do the
>>> above in the same directory is even smaller.
>>>
>>> Now admin scripts do have to handle the files created by the goofy users
>>> in the first category.
>>>
>>> Admin scripts don't ahve to worry about users creating a file
>>> called -, because admin scripts won't be run in the directory
>>> where the user did that. Not even scripts which do process
>>> paths traversing that directory. The admin (or cron, or systemd or
>>> whatever) will run those from somewhere else.
>>
>> Though I expect just about everyone has tried to run foo -xyz and
>> inadvertently run foo - xyz instead, ending up with a file named - and
>> one named xyz.
>
> $ rm -rf * .tmp
> rm: .tmp: No such file or directory
> $ unrm
> -ksh: unrm: not found
> $ man cpio

Spurious spaces are less common than this mistake, which I have seen
done by someone (who was at elevated privs at the time):

# rm *>o

(For those in exotic-keyboard-land: '>' was shifted '.', thus the
shift required for '*' hadn't been released yet.)

Phil
-- 
We are no longer hunters and nomads. No longer awed and frightened, as we have
gained some understanding of the world in which we live. As such, we can cast
aside childish remnants from the dawn of our civilization.
-- NotSanguine on SoylentNews, after Eugen Weber in /The Western Tradition/

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#172283

Fromkalevi@kolttonen.fi (Kalevi Kolttonen)
Date2023-08-15 14:30 +0000
Message-ID<ubg25m$2rr3g$1@dont-email.me>
In reply to#172239
In comp.unix.programmer Gary R. Schmidt <grschmidt@acm.org> wrote:
> On 15/08/2023 01:14, Kalevi Kolttonen wrote:
> Ahah!  You don't have users, do you?

No, I no longer have users. However, I used to have
50 000 - 60 000 users, but only a tiny minority
of them had Unix shell access. The vast majority
was email users.

I certainly never ever encountered anyone
with filename or email folder name being '-'.

> No doubt you also don't encounter filenames with 
> spaces in them, or carriage returns, or other
> garbage.

That is a terrible and unjustified comparison
as filenams with spaces are very common indeed.

The "problem" of having '-' as a filename is
a complete non-issue that only has theoretical
interest. On Unix, no matter which stdin 
convention you choose, you run the risk of 
someone having that convention as a filename.

On Unix, it used to be the case that only
NUL-characters and '/' were out of question. I
suppose some filesystems place more restrictions
on filenames nowadays.

br,
KK

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#172294

FromGiovanni <lsodgf0@home.net.it>
Date2023-08-15 17:14 +0200
Message-ID<ubg4no$8kb$1@milena.home.net.it>
In reply to#172283
On 8/15/23 16:30, Kalevi Kolttonen wrote:
> On Unix, it used to be the case that only
> NUL-characters and '/' were out of question. I
> suppose some filesystems place more restrictions
> on filenames nowadays.

There are still no restriction on file names. It`s only a problem of the 
program.  If it expects a file name as input, it has to test if the 
argument passed is - in which case it reads from stdin.  And, usually, 
this works even if the file system has in the current directory a file 
named -

To use the file - you should pass it to the program as ./-

Ciao
Giovanni
-- 
   A computer is like an air conditioner,
   it stops working when you open Windows.
   < https://giovanni.homelinux.net/ >

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#172302

Fromgazelle@shell.xmission.com (Kenny McCormack)
Date2023-08-15 15:48 +0000
Message-ID<ubg6o7$3jrsn$1@news.xmission.com>
In reply to#172294
In article <ubg4no$8kb$1@milena.home.net.it>,
Giovanni  <gfalzoni@inwind.it> wrote:
>On 8/15/23 16:30, Kalevi Kolttonen wrote:
>> On Unix, it used to be the case that only
>> NUL-characters and '/' were out of question. I
>> suppose some filesystems place more restrictions
>> on filenames nowadays.
>
>There are still no restriction on file names. It`s only a problem of the 
>program.  If it expects a file name as input, it has to test if the 
>argument passed is - in which case it reads from stdin.  And, usually, 
>this works even if the file system has in the current directory a file 
>named -
>
>To use the file - you should pass it to the program as ./-

Yes, as noted, you know that.

And I know that.

And even Kalevi knows that.

But do they know that???

-- 
The randomly chosen signature file that would have appeared here is more than 4
lines long.  As such, it violates one or more Usenet RFCs.  In order to remain
in compliance with said RFCs, the actual sig can be found at the following URL:
	http://user.xmission.com/~gazelle/Sigs/Aspergers

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#172311

Fromkalevi@kolttonen.fi (Kalevi Kolttonen)
Date2023-08-15 16:12 +0000
Message-ID<ubg853$2ssj8$1@dont-email.me>
In reply to#172302
Kenny McCormack <gazelle@shell.xmission.com> wrote:
> But do they know that???

"They" probably don't know it. But let's face it,
nobody really wants to create a file having '-'
filename on purpose. The filename is not descriptive
at all, it would be just an insane choice for anything
useful.

It could happen by accident, but even that is quite 
unlikely.

If "they" don't know how to delete it, there is no need
to panic. The file's existence does no harm. "They" can 
always ask for help and someone will tell them how
to get rid of it.

I guess the stdin convention '-' is decades old.
It was chosen because they had pick something that 
is short and not likely to exist as a real file.

br,
KK

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