How can I get perl to correctly pass a command line argument with multiple arguments and complex file paths (spaces and symbols)? - perl

Question

I have a small perl script which collects file paths from an excel file and passes them through the command line to perltex which then compiles a pdf based on the files and paths chosen.
My problem is that the moment I introduce more complex file paths (which is necessary based on the network setup of the final user pool) perltex fails to find the file paths, cutting them at the space.
A MWE is a follows
#!/usr/bin/perl
use strict;
use warnings;
use 5.14.2;
use Text::Template;
use Spreadsheet::Read;
use Spreadsheet::ParseXLSX;
use utf8;
use charnames qw( :full :short );
use autodie;
my $row = 5;
my $col = 15;
my $File = "C:/Users/me/Desktop/Reporting-Static/Input-test1.xlsm";
my $parser = Spreadsheet::ParseXLSX->new();
my $workbook = $parser->parse($File);
my $worksheet = $workbook->worksheet("Input");
my $cell = $worksheet->get_cell($row, $col);
my $Filename = $cell->Value();
my $texfile = "C:/Users/me/Desktop/Reporting-Static/file.tex";
# can't find this file if there are spaces in the address
system("perltex", "--latex=pdflatex", "--nosafe", "--jobname=$Filename", "$texfile");
if ( $? == -1 )
{
print "command failed: $!\n";
}
else
{
printf "command exited with value %d", $? >> 8;
}
exit;
However, the moment I change the folder name to one with spaces eg. "Reporting Static" it fails to find the tex file.
I have read several other posts regarding this on stack exchange and other websites but for whatever reason the proposed solutions do not appear to work for me. I have tried
my $texfile = "C:/Users/me/Desktop/Reporting Static/file.tex";
my $texfile = C:/Users/me/Desktop/"Reporting Static"/file.tex;
my $texfile = "\"C:/Users/me/Desktop/"Reporting Static"/file.tex\"";
my $texfile = "\"C:/Users/me/Desktop/Reporting Static/file.tex\"";
my $texfile = "C:/Users/me/Desktop/Reporting^ Static/file.tex";
my $texfile = "C:/Users/me/Desktop/Reporting\^ Static/file.tex";
As well as a few other combinations or varioations of the above, all without success. I have also tried replacing the double quote with a single quote so that perl doesn't interpolate the contents.
I have also tried manually typing all of the above into the command prompt to check whether there was a small issue with the way perl passed the commands to the command line but still no luck.
I am aware that I can use the 'dir /X ~1 c:\' command to find system name allocations that avoid spaces but the idea is that the filename and location will be dynamic and change as a funtion of department and site, so I would prefer to avoid trying to write a script which will go and find this pathname and use it to replace all locations using spaces or other special characters.
The final idea that I had is that this problem could be connected ot the way that perltex passes it's arguments yet I am unable to find any documentation (that I can follow...) on the specifics of how this particular aspect of the file functions.
So my questions are, is there something I am missing not metioned in the other answers that I have read regarding how to correctly pass these paths to perltex, is there perhaps some sort of incompatiblity in how I'm trying to go about this, is this more probabl linked to perltex as opposed to perl or cmd or is there something completely different that I am unaware of that is stopping this from working???
EDIT:
from cmd prompt perltex returns a "unable to find path X, please enter another file location". Until now I hadn't really tested retyping the path by by entering 'C:/Users/me/Desktop/"Reporting Static"/file.tex' (no quotes at the beginning) it is subsequently accepted and runs. but initially passing it this path does not work, suggesting that some internal perltex code accepts the inital path differently to being repassed the same path after an error.... not quite sure what to make of this.
EDIT:
The contents of #latexcmdline that I extracted
$VAR1 = [
'pdflatex',
'--jobname=--',
'\\makeatletter\\def\\plmac#tag{AYNNNUVKQVJGZKKPGPTH}\\def\\plmac#tofile{Perl.topl}\\def\\plmac#fromfile{Perl.frpl}\\def\\plmac#toflag{Perl.tfpl}\\def\\plmac#fromflag{Perl.ffpl}\\def\\plmac#doneflag{Perl.dfpl}\\def\\plmac#pipe{Perl.pipe}\\makeatother\\input C:/Users/me/Desktop/PERLTEST/Perl',
'Modules/RevuedeProjetDB.tex'
];
This was done by inserting
use File::Slurp;
use Data::Dumper;
write_file 'C:\Users\me\Desktop\PERLTEST\mydump.log', Dumper( \#latexcmdline );
before the exec command.

Answer 1

Update
I initially recommended that you should use String::ShellQuote but that module is for Linux only so I deleted my answer when I realised that your question was about the Windows system
It seems that there's also a Win32::ShellQuote which does the same thing for Windows, so I am renewing my suggestion
As I said before, the issue is that perltex itself doesn't properly handle paths containing whitespace, even if they are correctly passed as a single element of #ARGV. I believe the solution is to pass the path including enclosing quotes, although I have never been able to test this properly as I have no LaTex installation
Unfortunately, even if I pass qq{"$texfile"}, the quotes are still stripped before they reach the target program, so they must be protected in some way
You need the quote_system function from that module, which will prepare a list of strings so that they retain any quotation marks
Using a parameter of quote_system(qq{"$texfile"}) produces the correct result in my tests. It is the equivalent of passing qq{"\\"$texfile\\""} but less ugly
So your system call should be like this (with no modification to perltex.pl)
I have applied the same principle to $Filename as it may well be that this also contains whitespace
use Win32::ShellQuote 'quote_system';
system(quote_system(
'perltex',
'--latex=pdflatex',
'--nosafe',
qq{--jobname="$Filename"},
qq{"$texfile"},
));
Okay, well I have a solution of sorts
The issue, as I suspected, is that, although the path is passed as a single string to perltex.pl, the latter doesn't handle paths with spaces properly after it has received them
The temporary fix is to hack perltex.pl
Line 82 of my version of perltex.pl (there is no version number in the source) reads
$latexcmdline[$firstcmd] = "\\input $option";
If you change that to
$latexcmdline[$firstcmd] = qq{\\input "$option"};
then all should be well. However this is a solid fix only when it is distributed by the author of perltex. Meanwhile I am looking for a nicer solution from the calling side

Answer 2

There are two steps to solving this problem.
Work out how to get the correct arguments into an external
program.
Work out how to do that from a Perl program.
For step 1, I find a program like this to be useful.
#!/usr/bin/perl
use strict;
use warnings;
print "Received ", scalar #ARGV, " arguments:\n";
for (1 .. #ARGV) {
print "$_: $ARGV[$_ - 1]\n";
}
It just explains what arguments it receives on the command line. You can use this in place of "perltex" for testing purposes.
You'll see that if you give it an argument that contains spaces, then that is interpreted as the called program as multiple arguments. The way to get round that is to quote the argument that contains a space. And I seem to remember that Windows insists on double-quotes (for reasons that I can never remember).
So I think that you want this:
system('perltex', '--latex=pdflatex', '--nosafe', "--jobname=\"$Filename\"", "\"$texfile\"");
I've double-quoted both of the filenames. Of course, those escaped double-quote characters look really ugly, and Perl gives us qq(...) to make that look nicer.
system('perltex', '--latex=pdflatex', '--nosafe', qq(--jobname="$Filename"), qq("$texfile"));
If that's not quite right, then the program I showed earlier will make it easier to find the solution.
Update: Borodin's comment below about this making no difference to $texfile is accurate. The fact that we're passing a list to system() means that the shell isn't involved at all.