Problems with special characters in Linux file names

EigenFunctions has asked for the wisdom of the Perl Monks concerning the following question:

I write scripts in tcsh (sorry, not bash) and programs in Perl (in the past, I've written a lot in "C"). In both cases (tcsh and Perl), I have problems with filenames that contain special characters. I use (){}[]!# in most of my filenames and folder names, some of which came from the old days of windoz. My laptops run either Ubuntu or Debian and I use nautilus to access files and it understands these files and folder.

A Perl snippet as an example of the problem:

use String::ShellQuote;                        # this package almost n
+ever works

my $Temp = shell_quote_best_effort('BulletinV3, 1 Montana 20xx-xx-xx (
+print).pdf_FN_TEMPLATE');

if (-e $Temp) {
    `zenity --width 300 --info  --text 'DBG> Got it!'`;
    }
  else {
    `zenity --width 300 --error --text 'DBG> Nope, not found!'`; # thi
+s is what I get all the time
    }

$rc = rename("BulletinV3, 1 Montana 20xx-xx-xx (print).pdf_FN_TEMPLATE
+",
             "BulletinV3, 1 Montana $SundayDate (print).pdf_FN_TEMPLAT
+E");
if($rc == 1) {
    $ExtTypes{'pdf_FN_TEMPLATE'}++;
    }
  else {
    `zenity --title \"Rename problem\" --width 400 --error --text \"Fi
+le rename error (\\\"$!\\\"; \\\"BulletinV3, 1 Montana 20xx-xx-xx (pr
+int).pdf_FN_TEMPLATE\\\")\"`;
    }
[download]

I know the file is there, I can see it, I can show it with ls (on the command-line), but the Perl program does not. I've tried all manner of quoting with backslashes, single and double quotes etc. I've tried using back-ticks with Linux 'mv' commands instead of rename() but in all the cases, nothing works. I've been plagued with this problem for years and, sometimes, I can find unique ways to deal with it. I'd like a way that I can use for all situations (it seems, nautilus has a solution that works).

Any help would be greatly appreciated.

Thanks,
EigenFunctions
OpSys: Ubuntu 18.04; Perl: Perl 5, version 26, subversion 1 (v5.26.1) built for x86_64-linux-gnu-thread-multi (with 71 registered patches)

Comment on Problems with special characters in Linux file names Download Code

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Re: Problems with special characters in Linux file names by ikegami (Patriarch) on Sep 13, 2022 at 15:13 UTC
You use `shell_quote` where you shouldn't. (And, arguably, you don't use it where you should.) `-e` needs a path, not a piece of shell code. `my $src_qfn = 'BulletinV3, 1 Montana 20xx-xx-xx (print).pdf_FN_TEMPLAT +E'; if (-e $src_qfn) { ... } else { ... }` [download] Or with error checking: my $src_qfn = 'BulletinV3, 1 Montana 20xx-xx-xx (print).pdf_FN_TEMPLAT +E'; if ( stat( $src_qfn ) ) { ... } else { die( "Can't stat `$src_qfn`: $!\n" ) if !$!{ ENOENT }; ... } [download] As for that message of command at the bottom, system( "zenity", "--title" => "Rename problem", "--width" => 400, "--error", "--text" => "Can't rename `$src_qfn` to `$dst_qfn`: $!", ) [download]	[reply] [d/l] [select]
Re^2: Problems with special characters in Linux file names by EigenFunctions (Beadle) on Sep 13, 2022 at 15:32 UTC
I put the code snippet, which came directly from my program, into a file and, it works! There is so little code, I don't know how it works in one place and NOT the other. I'll post another comment as soon as I find what I did wrong. Sorry Thanks, EigenFunctions OpSys: Ubuntu 18.04; Perl: Perl 5, version 26, subversion 1 (v5.26.1) built for x86_64-linux-gnu-thread-multi (with 71 registered patches)	[reply]
Re^3: Problems with special characters in Linux file names by EigenFunctions (Beadle) on Sep 13, 2022 at 15:47 UTC
Sorry, sorry, sorry! Operator error! It wasn't the filename, the problem was I didn't include the path. I added the path and all is well. I'm so embarrassed. Please ignore this post! Thanks, EigenFunctions OpSys: Ubuntu 18.04; Perl: Perl 5, version 26, subversion 1 (v5.26.1) built for x86_64-linux-gnu-thread-multi (with 71 registered patches)	[reply]
Re^4: Problems with special characters in Linux file names by Your Mother (Archbishop) on Sep 14, 2022 at 10:45 UTC
Re: Problems with special characters in Linux file names by afoken (Chancellor) on Sep 13, 2022 at 18:30 UTC
`use String::ShellQuote; # this package almost n +ever works` [download] I couldn't agree more with that comment: Problems with String::ShellQuote Are you sure that tcsh uses the same quoting rules as bourne shells? If not, you are probably in trouble. I don't really know, but a quick Google search suggests that there are differences. I found a pirated copy of "Unix Power Tools" (third edition) that has an entire chapter named "Differences Between Bourne and C Shell Quoting". It lists three differences, of which at least two are relevant for String::ShellQuote. In csh, `!` can only be quoted by a backslash, it keeps its special meaning even inside single quotes. And the csh needs a backslash before newlines inside single and double quotes, unlike bourne shells. And by the way, shell_quote_best_effort() may damage data and hides errors. See Problems with String::ShellQuote. Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l] [select]
Re^2: Problems with special characters in Linux file names by ikegami (Patriarch) on Sep 18, 2022 at 21:01 UTC
Are you sure that tcsh uses the same quoting rules as bourne shells? If not, you are probably in trouble. This is completely bogus. `-e` does not use tcsh. Or any shell. Your entire post is a baseless irrelevant rant.	[reply] [d/l]
Re: Problems with special characters in Linux file names by Anonymous Monk on Sep 16, 2022 at 06:17 UTC
Have you considered using the built-in Perl fn readdir() & friends https://perldoc.perl.org/functions/readdir & Chap 9 of Perl cookbook? This would avoid you having to try and parse in the shell.	[reply]