Regular expression to shorten file paths - regex

I need to shorten file paths for a report I'm working on for NTFS and share permissions. I'm trying to remove for example \\ in share paths and C:\ in drive paths and replace any slashes thereafter with >. I also need to shorten the path down to just the last folder but taking into account spaces and special characters. Between the > and the folder name it needs a space.
So for example \\Finance\Accounts & Payroll\Sage becomes >> Sage.
And D:\HR\Personnel\Records\Holidays\2015 becomes >>>> 2015.

Here's a regex-based solution (that at least works with the sample data):
echo '\Finance\Accounts & Payroll\Sage
D:\HR\Personnel\Records\Holidays\2015' \
| perl -pe 's/(^|[^\\]+)\\+/>/g; s/(>*)>/$1 /'
↓
>> Sage
>>>> 2015
(No language was specified, so I just used my personal favourite. Most regex implementations should work, though.)
It's a bit of a hack. Another way would be something like (in pseudocode):
parts = split(/\\+/, path)
return ('>' × (parts.size - 2) ) ⌢ ' ' ⌢ parts[-1]
Keep in mind though that Windows (and others) generally accepts / as a separator as well. And that neither of the above take into account things like .. and \.\. Normalising the path first would be a good idea.

Related

replace part of file name with wrong encoding

Need some guidance how to solve this one. Have 10 000s of files in multiple subfolders where the encoding got screwed up. Via ls command I see a filename named like this 'F'$'\366''ljesedel.pdf', that includes the ' at beginning and end. That's just one example where the Swedish characters åäö got wrong, in this example this should have been 'Följesedel.pdf'. If If I run
#>find .
Then I see a list of files like this:
./F?ljesedel.pdf
Not the same encoding. How on earth solving this one? The most obvious ways:
myvar='$'\366''
char="ö"
find . -name *$myvar* -exec rename 's/$myvar/ö' {} \;
and other possible ways fails since
find . -name cannot find it due to the ? instead of the "real" characters " '$'\366'' "
Any suggestions or guidance would be very much appreciated.
The first question is what encoding your terminal expects. Make sure that is UTF-8.
Then you need to find what bytes the actual filename contains, not just what something might display it as. You can do this with a perl oneliner like follows, run in the directory containing the file:
perl -E'opendir my $dh, "."; printf "%s: %vX\n", $_, $_ for grep { m/jesedel\.pdf/ } readdir $dh'
This will output the filename interpreted as UTF-8 bytes (if you've set your terminal to that) followed by the hex bytes it actually contains.
Using that you can determine what your search pattern should be. Your replacement must be the UTF-8 encoded representation of ö, which it will be by default as part of the command arguments if your terminal is set to that.
I'm not an expert - but it might not be a problem with the file name (which seems to hold the correct Unicode file name) - but with the way ls (and many other utilities) show the name to the terminal.
I was able to show the correct name by setting the terminal character encoding to Unicode. Also I've noticed the GUI programs (file manager, etc), were able to show the correct file name.
Gnome Terminal: "Terminal .. set character encoding - Unicode UTF8
It is still a challenge with many utilities to 'select' those files (e.g., REGEXP, wildcard). In few cases, you will have to select those character using '*' pattern. If this is a major issue considering using Ascii only - may be use the 'o' instead of 'ö'. Not sure if this is acceptable.

bulk file renaming in bash, to remove name with spaces, leaving trailing digits

Can a bash/shell expert help me in this? Each time I use PDF to split large pdf file (say its name is X.pdf) into separate pages, where each page is one pdf file, it creates files with this pattern
"X 1.pdf"
"X 2.pdf"
"X 3.pdf" etc...
The file name "X" above is the original file name, which can be anything. It then adds one space after the name, then the page number. Page numbers always start from 1 and up to how many pages. There is no option in adobe PDF to change this.
I need to run a shell command to simply remove/strip out all the "X " part, and just leave the digits, like this
1.pdf
2.pdf
3.pdf
....
100.pdf ...etc..
Not being good in pattern matching, not sure what regular expression I need.
I know I need something like
for i in *.pdf; do mv "$i$" ........; done
And it is the ....... part I do not know how to do.
This only needs to run on Linux/Unix system.
Use sed..
for i in *.pdf; do mv "$i" $(sed 's/.*[[:blank:]]//' <<< "$i"); done
And it would be simple through rename
rename 's/.*\s//' *.pdf
You can remove everything up to (including) the last space in the variable with this:
${i##* }
That's "star space" after the double hash, meaning "anything followed by space". ${i#* } would remove up to the first space.
So run this to check:
for i in *.pdf; do echo mv -i -- "$i" "${i##* }" ; done
and remove the echo if it looks good. The -i suggested by Gordon Davisson will prompt you before overwriting, and -- signifies end of options, which prevents things from blowing up if you ever have filenames starting with -.
If you just want to do bulk renaming of files (or directories) and don't mind using external tools, then here's mine: rnm
The command to do what you want would be:
rnm -rs '/.*\s//' *.pdf
.*\s selects the part before (and with) the last white space and replaces it with empty string.
Note:
It doesn't overwrite any existing files (throws warning if it finds an existing file with the target name).
And this operation is failsafe. You can get back the changes made by last rnm command with rnm -u.
Here's a list of documents for rnm.

export filenames to temp file bash

I have a lot of files in multiple directories that all have the following setup for the filename:
prob123456_01
I want to delete the trailing "_01" off of each file name and export them to a temp file. How exactly would I delete the trailing "_01" as well as export? I am rather new to scripting so any help would be greatly appreciated!
As you've tagged with bash, I'll assume that you can use globstar
shopt -s globstar # enable globstar
for f in **_[0-9][0-9]; do echo "${f%_*}"; done > tmp
With globstar enabled, the pattern **_[0-9][0-9] matches any file ending in _, followed by any 2 digit number, in the current directory and any subdirectories. ${f%_*} removes the end of the file name using bash's built-in string manipulation functionality.
Better yet, as Charles Duffy suggests (thanks), you can use an array instead of a loop:
files=( **_[0-9][0-9] ); printf '%s\n' "${files[#]%_*}"
The array is filled the filenames that match the same pattern as before. ${files[#]%_*} removes the last part from each element of the array and passes them all as arguments to printf, which prints each result on a separate line.
Either of these approaches is likely to be quicker than using find as everything is done in the shell, without executing any separate processes.
Previously I had suggested to use the pattern **_{00..99}, although this is not ideal for a couple of reasons. It is less efficient, as it expands to **_00, **_01, **_02, ..., **_99. Also, any of those 100 patterns that don't match will be included literally in the output unless another option, nullglob is enabled.
It's up to you whether you use [0-9] or [[:digit:]] but the advantage of the latter is that it matches all characters defined to be a digit, which may vary depending on your locale. If this isn't a concern, I would go with the former.
If I understand you correctly, you want a list of the filenames without the trailing _01. The following would do that:
find . -type f -name '*_01' | sed 's/_01$//' > tmp.lst
find . -type f -name '*_01' looks for all the files in the current directory, and its descendent directories, for files with names ending in _01.
| is the so-called pipe, handing the results of the left-hand call to the right-hand call.
sed 's/_01$//' removes the _01 from the end of each filename.
> tmp.lst writes the result into the file tmp.lst
These are all pretty basic parts of working with bash and its likes, so it might be a good idea to look at a tutorial or two and familiarize yourself with those and a few others ;)

Specifying a range of files using regex

I have a huge amount of files (in the hundreds of thousands) that all have the same format of name.
The filename format is:
[prefix][number]suffix]
where the [prefix] and [suffix] of all the files is the same, and just the number part changes. The number part is something like 0004732
So the filenames are:
[prefix]004732[suffix]
[prefix]004733[suffix]
[prefix]004734[suffix]
etc.
I need to move a range of about 100,000 files (with consecutive numbers) to another directory, and I was wondering if it is possible to do this with a regular expression.
You're looking for character classes. It's a bit difficult to specify number ranges using regex because it works on text, not numbers, but it can be done something like this (for files 1-100):
prefix[0-1][0-9][0-9]suffix
prefix[0-1]\d\dsuffix #this also works in PERL regex
More complicated numbers get trickier. For 0-211:
prefix([0-1][0-9][0-9]|20[0-9]|21[0-1])suffix
If you're on Windows, install Cygwin, and do the following. If you're on Mac OS X or Linux, just open a terminal. You'll need to do the following:
ls PREFIX* | sed 's/PREFIX\(0[0-9]\)SUFFIX/mv & tmp\/PREFIX\1SUFFIX/' | sh
What is this doing?
Lists all files starting with the specified prefix
Pipes this list to sed, which uses a regex pattern to match only files that fall within the range you specify
Create a new string using the move command
Pipes the move command string to the shell (sh) and executes it
You can tweak the regex to match your number range by looking at the following:
http://www.regular-expressions.info/numericranges.html
To the best of my knowledge, there is no regex (to handle complex cases), but you can use loop easily:
The following code runs in linux. I ran simnilar code on Windows using CygWin and it works as well. Maybe there is similar way to do in Windows.
If the two numbers are with the same digits;
Example: from
[prefix]000012345[suffix]
to
[prefix]000056789[suffix]
:
for (( i=12345; i<56789; i++)); do mv "[prefix]0000$i[suffix]" /newDirectoryPath done
Otherwise you can do with multiple (usually two or three) commands;
Example: from
[prefix]000012345[suffix]
to
[prefix]003456789[suffix]
:
for (( i=12345; i<99999; i++)); do mv "[prefix]0000$i[suffix]" /newDirectoryPath done
for (( i=100000; i<999999; i++)); do mv "[prefix]000$i[suffix]" /newDirectoryPath done
for (( i=1000000; i<3456789; i++)); do mv "[prefix]00$i[suffix]" /newDirectoryPath done

Powershell: REGEXP to modify paths to different *nix styles

I'm using Rsync and ICACLS to sync two (windows) directories and to do so, I must the same path translated to several 'styles': cygwin *nix, remote *nix, UNC. (see examples below)
I'm using the following code to do so, and while it works, the regexp I'm using could be surely made more robust and better working (as you can see, I'm doing a replace of a replace, wich i find ugly at best...)
$remote="remotesrv"
$path="g:\tools\example\"
$local_dos=$path
$remote_dos="\\$remote\"+(($local_dos -replace "^\w","$&$") -replace "(:\\)|(\\)","\")
$local_nix="/cygdrive/"+($local_dos -replace "(:\\)|(\\)","/")
$remote_nix="//$remote/"+(($local_dos -replace "^\w","$&$") -replace "(:\\)|(\\)","/")
"Local DOS : $local_dos"
"Remote DOS : $remote_dos"
"Local *nix : $local_nix"
"Remote *nix: $remote_nix"
the output is:
Local DOS : g:\tools\example\
Remote DOS : \\remotesrv\g$\tools\example\
Local *nix : /cygdrive/g/tools/example/
Remote *nix: //remotesrv/g$/tools/example/
Can someone please help me with the regexes above? Many thanks!
How about this:
$local_dos = $path
$remote_dos = "\\$remote\$path" -replace ':', '$'
$local_nix = "/cygdrive/$path" -replace ':?\\', '/'
$remote_nix = "//$remote/$path" -replace ':?\\', '/'
The dos ones are pretty simple and aren't really using regex much.
For the nix ones, :?\\ means "\ optionally preceded by :". We're replacing that with a forward slash.
This should work fine for the vast majority of non-pathological cases. However, it's not bulletproof. Crazy file names with slashes or colons in them could easily break this.
The usual approach is to split a path into its component parts, translate the parts, then recombine the parts for the destination OS. For Windows/Cygwin/DOS, the component parts are:
Drive
Path
Filename (the part before the first '.' in most filesystems)
File extension(s) (where zim.tar.gz would have filename = zim and extension = .tar.gz)
Long-term, this is easier and faster than trying to do it all at once. (I know -- I've tried it all-at-once before.)
Perl's File::Spec modules may be worth a look for ideas if you can read Perl code.