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Hi there,

I am having problem in W2K when using Cygwin's Perl.
My Perl script starts Shell script with System -command;
system(scriptfile). The shell script creates a temporary file
like this:

#!/usr/bin/sh
cat "blah blah" > tempfile

and then exits back to Perl. When I then try to remove
the created "tempfile" from the same Perl script with
"unlink" I find out that Perl does not have access rights to the file.
If I use "readdir" Perl finds the file but nor command
"system(rm $file)" or "unlink($file)" does not work either. However,
when Perl script exits I can remove the file with
normal Bash shell command: "rm tempfile".

It seems that Perl is running with different user rights
than the Shell script. My question is therefore: "How can I remove file
created by the Bash shell script started as subshell from Perl script?"
Should I start another Shell script that executes "rm tempfile"
just for that task?

-pekka-

Pekka Niiranen <> wrote in comp.lang.perl.misc:
> Hi there,
>
> I am having problem in W2K when using Cygwin's Perl.
> My Perl script starts Shell script with System -command;
> system(scriptfile). The shell script creates a temporary file
> like this:
>
> #!/usr/bin/sh
> cat "blah blah" > tempfile
>
> and then exits back to Perl. When I then try to remove
> the created "tempfile" from the same Perl script with
> "unlink" I find out that Perl does not have access rights to the file.

So what *are* the permissions and ownership of the file? What
does "ls -l" say? You are not giving us vital information.

> If I use "readdir" Perl finds the file but nor command
> "system(rm $file)" or "unlink($file)" does not work either. However,

Does $file contain what you think it does?

> when Perl script exits I can remove the file with
> normal Bash shell command: "rm tempfile".
>
> It seems that Perl is running with different user rights
> than the Shell script. My question is therefore: "How can I remove file
> created by the Bash shell script started as subshell from Perl script?"

No idea. Show complete code that demonstrates the problem.

Anno

Pekka Niiranen <> wrote in news:4100130f$0
$13046$:

> and then exits back to Perl. When I then try to remove
> the created "tempfile" from the same Perl script with
> "unlink" I find out that Perl does not have access rights to the file.
> If I use "readdir" Perl finds the file but nor command
> "system(rm $file)" or "unlink($file)" does not work either. However,
> when Perl script exits I can remove the file with
> normal Bash shell command: "rm tempfile".
>
> It seems that Perl is running with different user rights

I find that highly unlikely.

> than the Shell script. My question is therefore: "How can I remove file
> created by the Bash shell script started as subshell from Perl script?"
> Should I start another Shell script that executes "rm tempfile"
> just for that task?

In addition to Anno's suggestions, I have one question. Do you read from
the tempfile in your Perl script. If you do, does your script close the
file handle before attempting to call unlink?

--
A. Sinan Unur
d
(remove '.invalid' and reverse each component for email address)

Ok here goes,

---the perl script named "p" starts--
#!/usr/local/bin/perl -w
unless (opendir(TMPDIR, "/cygdrive/c/home/cygwin/tmp")) {
print "Can't open temporary directory !";
}
system("/cygdrive/c/home/cygwin/s"); # run the shell script
while( defined ($tmpfile = readdir TMPDIR) ) {
next if $tmpfile =~ /^\.\.?$/;
system("chmod 660 $tmpfile") or die;
}
system("ls -l ./tmp");
closedir(TMPDIR);

---the perl script named "p" stops---

---the bash script named "s" starts---

#!/usr/bin/bash
echo "Blah Blah" > ./tmp/tfile
exit
---the bash script named "s" stops---

The perl script and shell script are run from the same directory.
The file "tfile" is created into subdirectory "tmp"

"ls -l" from script directory gives (among other things):
drwxr-xr-x+ 2 treniira Administ 0 Jul 23 12:11 tmp/

Perl scripts output is:
[vat58008:~] $ ./p
chmod: getting attributes of `tfile': No such file or directory
total 1
-rw-r--r-- 1 treniira Administ 10 Jul 23 12:23 tfile


-pekka-

Anno Siegel wrote:
> Pekka Niiranen <> wrote in comp.lang.perl.misc:
>
>>Hi there,
>>
>>I am having problem in W2K when using Cygwin's Perl.
>>My Perl script starts Shell script with System -command;
>>system(scriptfile). The shell script creates a temporary file
>>like this:
>>
>>#!/usr/bin/sh
>>cat "blah blah" > tempfile
>>
>>and then exits back to Perl. When I then try to remove
>>the created "tempfile" from the same Perl script with
>>"unlink" I find out that Perl does not have access rights to the file.
>
>
> So what *are* the permissions and ownership of the file? What
> does "ls -l" say? You are not giving us vital information.
>
>
>>If I use "readdir" Perl finds the file but nor command
>>"system(rm $file)" or "unlink($file)" does not work either. However,
>
>
> Does $file contain what you think it does?
>
>
>>when Perl script exits I can remove the file with
>>normal Bash shell command: "rm tempfile".
>>
>>It seems that Perl is running with different user rights
>>than the Shell script. My question is therefore: "How can I remove file
>>created by the Bash shell script started as subshell from Perl script?"
>
>
> No idea. Show complete code that demonstrates the problem.
>
> Anno

Got it,

"readdir" does not return the full path;
I must built the full path to the file when calling "system":
system("chmod 660 <add path here>/$tmpfile")

Thanks anyway,

-pekka-

pekka niiranen wrote:

> Ok here goes,
>
> ---the perl script named "p" starts--
> #!/usr/local/bin/perl -w
> unless (opendir(TMPDIR, "/cygdrive/c/home/cygwin/tmp")) {
> print "Can't open temporary directory !";
> }
> system("/cygdrive/c/home/cygwin/s"); # run the shell script
> while( defined ($tmpfile = readdir TMPDIR) ) {
> next if $tmpfile =~ /^\.\.?$/;
> system("chmod 660 $tmpfile") or die;
> }
> system("ls -l ./tmp");
> closedir(TMPDIR);
>
> ---the perl script named "p" stops---
>
> ---the bash script named "s" starts---
>
> #!/usr/bin/bash
> echo "Blah Blah" > ./tmp/tfile
> exit
> ---the bash script named "s" stops---
>
> The perl script and shell script are run from the same directory.
> The file "tfile" is created into subdirectory "tmp"
>
> "ls -l" from script directory gives (among other things):
> drwxr-xr-x+ 2 treniira Administ 0 Jul 23 12:11 tmp/
>
> Perl scripts output is:
> [vat58008:~] $ ./p
> chmod: getting attributes of `tfile': No such file or directory
> total 1
> -rw-r--r-- 1 treniira Administ 10 Jul 23 12:23 tfile
>
>
> -pekka-
>
> Anno Siegel wrote:
>
>> Pekka Niiranen <> wrote in
>> comp.lang.perl.misc:
>>
>>> Hi there,
>>>
>>> I am having problem in W2K when using Cygwin's Perl.
>>> My Perl script starts Shell script with System -command;
>>> system(scriptfile). The shell script creates a temporary file
>>> like this:
>>>
>>> #!/usr/bin/sh
>>> cat "blah blah" > tempfile
>>>
>>> and then exits back to Perl. When I then try to remove
>>> the created "tempfile" from the same Perl script with
>>> "unlink" I find out that Perl does not have access rights to the file.
>>
>>
>>
>> So what *are* the permissions and ownership of the file? What
>> does "ls -l" say? You are not giving us vital information.
>>
>>
>>> If I use "readdir" Perl finds the file but nor command
>>> "system(rm $file)" or "unlink($file)" does not work either. However,
>>
>>
>>
>> Does $file contain what you think it does?
>>
>>
>>> when Perl script exits I can remove the file with
>>> normal Bash shell command: "rm tempfile".
>>>
>>> It seems that Perl is running with different user rights
>>> than the Shell script. My question is therefore: "How can I remove
>>> file created by the Bash shell script started as subshell from Perl
>>> script?"
>>
>>
>>
>> No idea. Show complete code that demonstrates the problem.
>>
>> Anno

Please don't top-post. I moved your reply in context.

pekka niiranen <> wrote in comp.lang.perl.misc:
> Anno Siegel wrote:
> > Pekka Niiranen <> wrote in comp.lang.perl.misc:
> >
> >>Hi there,
> >>
> >>I am having problem in W2K when using Cygwin's Perl.
> >>My Perl script starts Shell script with System -command;
> >>system(scriptfile). The shell script creates a temporary file
> >>like this:
> >>
> >>#!/usr/bin/sh
> >>cat "blah blah" > tempfile
> >>
> >>and then exits back to Perl. When I then try to remove
> >>the created "tempfile" from the same Perl script with
> >>"unlink" I find out that Perl does not have access rights to the file.
> >
> >
> > So what *are* the permissions and ownership of the file? What
> > does "ls -l" say? You are not giving us vital information.
> >
> >
> >>If I use "readdir" Perl finds the file but nor command
> >>"system(rm $file)" or "unlink($file)" does not work either. However,
> >
> >
> > Does $file contain what you think it does?
> >
> >
> >>when Perl script exits I can remove the file with
> >>normal Bash shell command: "rm tempfile".
> >>
> >>It seems that Perl is running with different user rights
> >>than the Shell script. My question is therefore: "How can I remove file
> >>created by the Bash shell script started as subshell from Perl script?"
> >
> >
> > No idea. Show complete code that demonstrates the problem.
> >
> > Anno


> Ok here goes,
>
> ---the perl script named "p" starts--
> #!/usr/local/bin/perl -w
> unless (opendir(TMPDIR, "/cygdrive/c/home/cygwin/tmp")) {
> print "Can't open temporary directory !";
> }

Checking "opendir" for errors is good.

> system("/cygdrive/c/home/cygwin/s"); # run the shell script

Not checking "system" for errors is not so good.

> while( defined ($tmpfile = readdir TMPDIR) ) {
> next if $tmpfile =~ /^\.\.?$/;
> system("chmod 660 $tmpfile") or die;

That won't work, unless your current directory happens to be
/cygdrive/c/home/cygwin/tmp, where the file is. That's the
reason for your error. Instead use

chmod 0660, "/cygdrive/c/home/cygwin/tmp/$tmpfile" or die "chmod";

Note that I replaced the system call with Perl's internal chmod.

> }
> system("ls -l ./tmp");
> closedir(TMPDIR);

[snip]

Anno

Anno Siegel wrote:
>
> pekka niiranen <> wrote in comp.lang.perl.misc:
>
>> print "Can't open temporary directory !";
>
> Checking "opendir" for errors is good.

Yes, and reporting the cause of those errors is even better:

print "Can't open temporary dir: $!";

sherm--

--
Cocoa programming in Perl: http://camelbones.sourceforge.net
Hire me! My resume: http://www.dot-app.org

pekka niiranen wrote:

> unless (opendir(TMPDIR, "/cygdrive/c/home/cygwin/tmp")) {
> print "Can't open temporary directory !";
> }
> system("/cygdrive/c/home/cygwin/s"); # run the shell script
> while( defined ($tmpfile = readdir TMPDIR) ) {

It is not a good idea to opendir a directory before creating a new
file in that directory. The readdir() may or may not see the new file.

Any time you opendir a directory other than '.', you must remember
to prepend the directory path to whatever readdir() returns.

system("/home/cygwin/s"); # Use the cygwin name not windows name
$dir = "/home/cygwin/tmp"; # Use the cygwin name not windows name
open(TMPDIR,$dir) or die "Cannot open directory $dir: $!";
while (defined ($dir_entry = readdir TMPDIR) ) {
$tmpfile = "$dir/$dir_entry";
...
}

-Joe