From adavies@ptc.com

Howdy All.

On Windows XP i've seen File​::Find​::find fail with​:

  Can't cd to /dir/xxx/####../../..

where the #'s are a long filename (~256 characters)

[Also note the error message does not include a separating '/'
between the dir_name and ../../..'s, or the $!]

It looks like chdir() is hitting some kind of too long pathname issue.

Here's a testcase that shows the problem​:

# %<
use File​::Find;

chdir '/' or die $!;

my $root_dir = '/long_dir_test';

-d $root_dir || mkdir($root_dir) || die "can't mkdir $root_dir​: $!\n";

# Make a maximally length named directory
# Problem seems to be filename length sensitive
foreach my $dir_name ('d', 'di', 'dir') {
  chdir($root_dir) or die "can't chdir to $root_dir​: $!\n";
  while (mkdir $dir_name) {
  chdir $dir_name or last;
  }
}

chdir('/') || die "can't chdir to /​: $!\n";

File​::Find​::find(sub {}, $root_dir); # this should die
# >%

By changing the code in File​::Find to do multiple individual
chdir("..")'s, it does not seem to hit the problem.
The following minimal patch shows what i mean​:

  while ( defined ($SE = pop @​Stack) ) {
  ($Level, $p_dir, $dir_rel, $nlink) = @​$SE;
  if ($CdLvl > $Level && !$no_chdir) {
+ if ($^O eq 'MSWin32') {
+ my $depth = $CdLvl - $Level;
+ while ($depth--) {
+ chdir("..") or die "Could not cd back to $dir_name​:
$!\n";
+ }
+ } else {
  my $tmp;
  if ($Is_MacOS) {
  $tmp = ('​:' x ($CdLvl-$Level)) . '​:';
@​@​ -939,6 +945,7 @​@​
  }
  die "Can't cd to $dir_name" . $tmp
  unless chdir ($tmp);
+ }
  $CdLvl = $Level;
  }

I'm not sure how this affects performance - probably for the worse :-(
Perhaps a better fix would use the lengths of $cwd and $dir_name
to determine if multiple chdir("..")s were needed.

Cheers, alex.

From adavies@ptc.com

Created by adavies@ptc.com

On Windows XP i've seen File​::Find​::find fail with​:

  Can't cd to /dir/####../../..

where the #'s are a long filename (~256 characters)

[Also note the error message does not include a separating '/'
between the dir_name and ../../..'s, or the value of $!, which
happens to be 'No such file or directory'.]

It looks like chdir("../../../..") is hitting some kind of
too long pathname issue.

Here's a testcase that shows the problem​:

# %<
use File​::Find;

chdir '/' or die $!;

my $root_dir = '/long_dir_test';

-d $root_dir || mkdir($root_dir) || die "can't mkdir $root_dir​: $!\n";

# Make a maximally length named directory
# Problem seems to be filename length sensitive
foreach my $dir_name ('d', 'di', 'dir') {
  chdir($root_dir) or die "can't chdir to $root_dir​: $!\n";
  while (mkdir $dir_name) {
  chdir $dir_name or last;
  }
}

chdir('/') || die "can't chdir to /​: $!\n";

File​::Find​::find(sub {}, $root_dir); # this should die
# >%

By changing the code in File​::Find to do multiple individual
chdir("..")'s, it does not seem to hit the problem.
The following minimal patch shows what i mean​:

  while ( defined ($SE = pop @​Stack) ) {
  ($Level, $p_dir, $dir_rel, $nlink) = @​$SE;
  if ($CdLvl > $Level && !$no_chdir) {
+ if ($^O eq 'MSWin32') {
+ my $depth = $CdLvl - $Level;
+ while ($depth--) {
+ chdir("..") or die "Could not cd back to $dir_name​:
$!\n";
+ }
+ } else {
  my $tmp;
  if ($Is_MacOS) {
  $tmp = ('​:' x ($CdLvl-$Level)) . '​:';
@​@​ -939,6 +945,7 @​@​
  }
  die "Can't cd to $dir_name" . $tmp
  unless chdir ($tmp);
+ }
  $CdLvl = $Level;
  }

I'm not sure how this affects performance - probably for the worse :-(
It might be possible to use the value of C< length($cwd) +
length($dir_name) >
to determine if multiple chdir("..")s were needed.

Cheers, alex.

Flags:
    category=library
    severity=low

Site configuration information for perl v5.8.7:

Configured by adavies at Thu Aug 11 14:02:10 2005.

Summary of my perl5 (revision 5 version 8 subversion 7) configuration:
  Platform:
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    uname=''
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    usethreads=define use5005threads=undef useithreads=define
usemultiplicity=define
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cl', ccflags ='-nologo -Gf -W3 -MD -DNDEBUG -O1 -DWIN32
-D_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT  -DPERL_IMPLICIT_CONTEXT
-DPERL_IMPLICIT_SYS -DUSE_PERLIO -DPERL_MSVCRT_READFIX',
    optimize='-MD -DNDEBUG -O1',
    cppflags='-DWIN32'
    ccversion='12.00.8804', gccversion='', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='__int64',
lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='link', ldflags ='-nologo -nodefaultlib -release
-libpath:"c:\perl3\lib\CORE"  -machine:x86'
    libpth=\lib
    libs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool.lib
comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib
netapi32.lib uuid.lib ws2_32.lib mpr.lib winmm.lib  version.lib
odbc32.lib odbccp32.lib msvcrt.lib
    perllibs=  oldnames.lib kernel32.lib user32.lib gdi32.lib
winspool.lib  comdlg32.lib advapi32.lib shell32.lib ole32.lib
oleaut32.lib  netapi32.lib uuid.lib ws2_32.lib mpr.lib winmm.lib
version.lib odbc32.lib odbccp32.lib msvcrt.lib
    libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl58.lib
    gnulibc_version='undef'
  Dynamic Linking:
    dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags='-dll -nologo -nodefaultlib -release
-libpath:"c:\perl3\lib\CORE"  -machine:x86'

Locally applied patches:
    


@INC for perl v5.8.7:
    C:/perl3/lib
    C:/perl3/site/lib
    .


Environment for perl v5.8.7:
    HOME=C:\alex
    LANG (unset)
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
 
PATH=C:\WINNT\system32;C:\WINNT;C:\WINNT\System32\Wbem;C:\perl3\bin;D:\a
lex\bin;C:\cygwin\bin;C:\Program Files\Perforce;C:\Program
Files\Microsoft Visual Studio\VC98\Bin;C:\Program Files\Microsoft Visual
Studio\Common\MSDev98\Bin
    PERL_BADLANG (unset)
    SHELL (unset)

From @rgs

On 21/08/07, via RT Davies, Alex <perlbug-followup@​perl.org> wrote​:

On Windows XP i've seen File​::Find​::find fail with​:

Can't cd to /dir/####../../..

where the #'s are a long filename (~256 characters)

[Also note the error message does not include a separating '/'
between the dir_name and ../../..'s, or the value of $!, which
happens to be 'No such file or directory'.]

It looks like chdir("../../../..") is hitting some kind of
too long pathname issue.

It's probably better to fix it in chdir() instead of putting a
work-around in File​::Find. Can this bug be reproduced without
File​::Find?

The RT System itself - Status changed from 'new' to 'open'