How can I opendir, replace all files containing a space with .?

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

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Re: How can I opendir, replace all files containing a space with .? by VSarkiss (Monsignor) on Aug 15, 2001 at 00:29 UTC
Single-character substitution is usually easiest with `tr`: `my ($filename, $newfile); foreach $filename (readdir(DIR)) { ($newfile = $filename) =~ tr/ /./; rename($filename, $newfile); }` [download] As a bonus, this will replace every space with a period. (That is a bonus, right? ;-) Also, you want to either chdir to the target directory, or prepend the directory name to the file names. When possible, I prefer `chdir`: `chdir $dir or die "Can't chdir to $dir: $!\n"; opendir(DIR, '.') or die "Can't open '.': $!\n";` [download] HTH	[reply] [d/l] [select]
Re: How can I opendir, replace all files containing a space with .? by maverick (Curate) on Aug 14, 2001 at 23:27 UTC
change `if (/ /) { $newfile =~ s/$.$ $.$/\./;` [download] to `if ($filename =~ / /) { $newfile = $filename; $newfile =~ s/ /./g;` [download] and you should be good to go. /\/\averick perl -l -e "eval pack('h','072796e6470272f2c5f2c5166756279636b672');"	[reply] [d/l] [select]
Re: How can I opendir, replace all files containing a space with .? by runrig (Abbot) on Aug 15, 2001 at 02:58 UTC
This is a bit overkill for just renaming files in a directory, but if you want to rename files in a directory and all subdirectories (or rename directories also), you can modify the first two lines of the sub: `use File::Find; my @dirs = qw(.); find( sub{ return if $File::Find::name eq $File::Find::topdir; $File::Find::prune=1, return if -d; if ((my $newname = $_) =~ tr/ /./) { print "Renaming $File::Find::name to $newname\n"; rename $_, $newname or die "Can't rename $_: $!"; } }, @dirs);` [download]	[reply] [d/l]
Re: How can I opendir, replace all files containing a space with .? by busunsl (Vicar) on Aug 15, 2001 at 10:43 UTC
In addition to what's been said already: Your code looks like you try to replace any number of spaces by one dot. If you want to replace one or more spaces by one dot, `tr/ /./` will not work. You have to use `s/ +/./g`	[reply] [d/l] [select]
Re: How can I opendir, replace all files containing a space with .? by Hofmator (Curate) on Aug 15, 2001 at 15:13 UTC
You already have gotten working but let me tell 'tear apart' your code, to tell you what went wrong. You should see this as a chance to learn, no offence meant. I put some comments into your sourcecode, always above the line which they belong to: # good, open with error checking opendir(DIR, "$dir") \|\| die "can't open $dir $!\n"; # maybe name the variable @filenames - as there is more than one # or get rid of the variable altogether by saying # foreach my $oldname ( readdir(DIR) ) my @filename = readdir (DIR); # declare filename with my and give better name (see above) # foreach my $oldname (@filename) foreach $filename (@filename) { # this matches against the special variable $_ # (which you are not using) you want # if ($filename =~ / /) if (/ /) { # the regex is completely wrong you want either # s/ +/./g or tr/ /./ try to figure out the difference # and $newfile is never assigned a value so: my $newfile = $oldfile; $newfile =~ s/ +/./g; # you don't have to do the rename when you didn't # change anything, so rename($oldname, $newfile) unless $oldname eq $newfile; } } closedir(DIR); [download] If you want to use this as a standalone script, I'd go for the rename program out of the Cookbook (recipe 9.9): `#!/usr/bin/perl -w # rename - Larry's filename fixer $op = shift or die "Usage: rename expr [files]\n"; chomp(@ARGV = <STDIN>) unless @ARGV; for (@ARGV) { $was = $_; eval $op; die $@ if $@; rename($was,$_) unless $was eq $_; }` [download] which can be used e.g. in the following ways (also from the Cookbook) `% rename 's/\.orig$//' .orig % rename 'tr/A-Z/a-z/ unless /^Make/' % rename '$_ .= ".bad"' .f % rename 'print "$_: "; s/foo/bar/ if <STDIN> =~ /^y/i' % find /tmp -name '~' -print \| rename 's/^(.+)~$/.#$1/'` [download] This approach has several advantages, as you can specify the affected files from the command line (and don't have to work on all files in a directory). Furthermore it is very flexible due to the eval approach. Your problem could be solved with it like this: `% rename 's/ +/./g' or % rename 'tr/ /./' *` [download] Try to understand how this program works - and if you have any questions, feel free to ask here ... -- Hofmator	[reply] [d/l] [select]
Re: Re: How can I opendir, replace all files containing a space with .? by nkpgmartin (Sexton) on Aug 15, 2001 at 19:02 UTC
Thanks! I appreciate the dissection. Maybe I'm just missing something, but while my script now does create a file with the . instead of the space, that file is empty. So its doing a "touch" rather than a "mv" and that is using open(NEW, ">>Test/$newfile"); what am I missing?	[reply]
Re3: How can I opendir, replace all files containing a space with .? by Hofmator (Curate) on Aug 15, 2001 at 20:22 UTC
In what way are you doing an `open(NEW, ">>Test/$newfile")` call - I thought you are renaming files with rename?? Could you post the code you have now, please. -- Hofmator	[reply] [d/l]
Re: Re3: How can I opendir, replace all files containing a space with .? by nkpgmartin (Sexton) on Aug 15, 2001 at 20:37 UTC
Re5: How can I opendir, replace all files containing a space with .? by Hofmator (Curate) on Aug 15, 2001 at 20:50 UTC
Some notes below your chosen depth have not been shown here
Re: How can I opendir, replace all files containing a space with .? by mugwumpjism (Hermit) on Aug 16, 2001 at 02:51 UTC
Hmm. Be careful with this script (once corrected) - if you have two files "`legalise cannabis`" and "`legalise.cannabis"`, the first file will be renamed on top of the second one! I'd change the middle of your loop to: `if (-e $newfile) { print STDERR ("Warning: $filename would " ."clobber $newfile, skipping\n"); } else { rename($filename, $newfile); }` [download]	[reply] [d/l]