Looks like a bug to me.
Linux:
>uname -a Linux enterprise 2.6.37.6-foken #2 SMP Sun Aug 14 02:20:59 CEST 2011 x +86_64 AMD Athlon(tm) II Neo N36L Dual-Core Processor AuthenticAMD GNU +/Linux >perl -E '$file=q[""]; say (-e($file) ? "yes" : "no")' no >perl -V Summary of my perl5 (revision 5 version 12 subversion 3) configuration +: Platform: osname=linux, osvers=2.6.35.10, archname=x86_64-linux-thread-multi uname='linux midas64 2.6.35.10 #2 smp thu jan 6 19:06:19 cst 2011 +x86_64 amd athlon(tm) ii x2 235e processor authenticamd gnulinux ' config_args='-de -Dprefix=/usr -Dvendorprefix=/usr -Dcccdlflags=-f +PIC -Dinstallprefix=/usr -Dlibpth=/usr/local/lib64 /usr/lib64 /lib64 +-Doptimize=-O2 -fPIC -Dusethreads -Duseithreads -Dpager=/usr/bin/less + -isr -Dinc_version_list=5.12.2 5.12.1 5.12.0 5.10.1 5.10.0 5.8.8 5.8 +.7 5.8.6 5.8.5 5.8.4 5.8.3 5.8.2 5.8.1 5.8.0 -Darchname=x86_64-linux' hint=recommended, useposix=true, d_sigaction=define useithreads=define, usemultiplicity=define useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=und +ef use64bitint=define, use64bitall=define, uselongdouble=undef usemymalloc=n, bincompat5005=undef Compiler: cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing + -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_ +FILE_OFFSET_BITS=64', optimize='-O2 -fPIC', cppflags='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -f +stack-protector -I/usr/local/include' ccversion='', gccversion='4.5.2', gccosandvers='' intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1 +6 ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', + lseeksize=8 alignbytes=8, prototype=define Linker and Libraries: ld='cc', ldflags =' -fstack-protector' libpth=/usr/local/lib64 /usr/lib64 /lib64 libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lpthread -lc perllibs=-lnsl -ldl -lm -lcrypt -lutil -lpthread -lc libc=/lib64/libc-2.12.2.so, so=so, useshrplib=false, libperl=libpe +rl.a gnulibc_version='2.12.2' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E' cccdlflags='-fPIC', lddlflags='-shared -O2 -fPIC -fstack-protector +' Characteristics of this binary (from libperl): Compile-time options: MULTIPLICITY PERL_DONT_CREATE_GVSV PERL_IMPLICIT_CONTEXT PERL_MALLOC_WRAP USE_64_ +BIT_ALL USE_64_BIT_INT USE_ITHREADS USE_LARGE_FILES USE_PERLIO USE_PERL_ATOF USE_REENTRANT_API Built under linux Compiled at Jan 26 2011 12:39:46 %ENV: PERL_UNICODE="SDL" @INC: /usr/lib64/perl5/site_perl/5.12.3/x86_64-linux-thread-multi /usr/lib64/perl5/site_perl/5.12.3 /usr/lib64/perl5/vendor_perl/5.12.3/x86_64-linux-thread-multi /usr/lib64/perl5/vendor_perl/5.12.3 /usr/lib64/perl5/5.12.3/x86_64-linux-thread-multi /usr/lib64/perl5/5.12.3 /usr/lib64/perl5/site_perl /usr/lib64/perl5/vendor_perl .
Windows:
C:\Users\alex>perl -E "$file=chr(34).chr(34); say $file.' '.(-e($file) + ? 'yes' : 'no')" "" yes C:\Users\alex>ver Microsoft Windows [Version 6.1.7601] C:\Users\alex>dir Volume in drive C is System Volume Serial Number is B663-2E5B Directory of C:\Users\alex 24.06.2012 19:12 <DIR> . 24.06.2012 19:12 <DIR> .. 25.05.2012 23:46 <DIR> .gegl-0.0 24.06.2012 19:21 <DIR> .gimp-2.6 24.06.2012 19:12 6.262 .recently-used.xbel 28.05.2012 14:19 <DIR> .thumbnails 06.05.2012 23:44 <DIR> Contacts 24.06.2012 19:12 <DIR> Desktop 24.06.2012 19:41 <DIR> Documents 01.07.2012 19:22 <DIR> Downloads 24.06.2012 19:32 <DIR> Favorites 06.05.2012 23:44 <DIR> Links 16.06.2012 12:54 <DIR> Music 25.05.2012 23:50 <DIR> Pictures 06.05.2012 23:44 <DIR> Saved Games 06.05.2012 23:44 <DIR> Searches 06.05.2012 23:44 <DIR> Videos 15.06.2012 21:05 <DIR> Virtual Machines 1 File(s) 6.262 bytes 17 Dir(s) 11.921.534.976 bytes free C:\Users\alex>perl -V Summary of my perl5 (revision 5 version 14 subversion 2) configuration +: Platform: osname=MSWin32, osvers=4.0, archname=MSWin32-x64-multi-thread uname='Win32 strawberryperl 5.14.2.1 #1 Tue Nov 22 22:40:59 2011 x +64' config_args='undef' hint=recommended, useposix=true, d_sigaction=undef useithreads=define, usemultiplicity=define useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=und +ef use64bitint=define, use64bitall=undef, uselongdouble=undef usemymalloc=n, bincompat5005=undef Compiler: cc='gcc', ccflags =' -s -O2 -DWIN32 -DWIN64 -DCONSERVATIVE -DPERL +_TEXTMODE_SCRIPTS -DUSE_SITECUSTOMIZE -DPERL_IMPLICIT_CONTEXT -DPERL_ +IMPLICIT_SYS -fno-strict-aliasing -mms-bitfields', optimize='-s -O2', cppflags='-DWIN32' ccversion='', gccversion='4.4.7', gccosandvers='' intsize=4, longsize=4, ptrsize=8, doublesize=8, byteorder=12345678 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1 +2 ivtype='long long', ivsize=8, nvtype='double', nvsize=8, Off_t='lo +ng long', lseeksize=8 alignbytes=8, prototype=define Linker and Libraries: ld='g++', ldflags ='-s -L"C:\strawberry\perl\lib\CORE" -L"C:\straw +berry\c\lib"' libpth=C:\strawberry\c\lib C:\strawberry\c\x86_64-w64-mingw32\lib libs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 +-ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -l +mpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32 perllibs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdl +g32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_3 +2 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32 libc=, so=dll, useshrplib=true, libperl=libperl514.a gnulibc_version='' Dynamic Linking: dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' ' cccdlflags=' ', lddlflags='-mdll -s -L"C:\strawberry\perl\lib\CORE +" -L"C:\strawberry\c\lib"' Characteristics of this binary (from libperl): Compile-time options: MULTIPLICITY PERL_DONT_CREATE_GVSV PERL_IMPLICIT_CONTEXT PERL_IMPLICIT_SYS PERL_MALLOC_WRAP PERL_PRESERVE_IVUV PL_OP_SLAB +_ALLOC USE_64_BIT_INT USE_ITHREADS USE_LARGE_FILES USE_PERLIO USE_PERL_ATOF USE_SITECUSTOMIZE Built under MSWin32 Compiled at Nov 22 2011 22:53:05 %ENV: PERL_JSON_BACKEND="JSON::XS" PERL_YAML_BACKEND="YAML" @INC: C:/strawberry/perl/site/lib C:/strawberry/perl/vendor/lib C:/strawberry/perl/lib . C:\Users\alex>
Even shorter:
C:\Users\alex>perl -E "stat(chr(34).chr(34)) or die $!; say 'huh?'" huh? C:\Users\alex>
vs.
>perl -E 'stat(q[""]) or die $!; say "huh?"' No such file or directory at -e line 1. >
If stat is successful, what is in stat()s return value?
C:\Users\alex>perl -MData::Dumper -E "@a=stat(chr(34).chr(34)) or die +$!; say Du mper(\@a)" $VAR1 = [ 2, # device 0, # inode 16895, # mode = 0x41FF = 040777 1, # nlink 0, # uid 0, # gid 2, # rdev 0, # size 1340557931, # atime 1340557931, # mtime 1336337436, # ctime '', # blocksize '' # blocks ]; C:\Users\alex>
Mode 0777 happens on Windows only for executables (by extension) and for directories. The bit 040000 looks like the directory flag. This fits the picture, because there is no executable extension in the file name.
Maybe some routine burried deep inside Perl, MinGW or Windows unquotes filenames? Let's look at the stat() output for "." and "..":
C:\Users\alex>perl -MData::Dumper -E "for $x (chr(34).chr(34),'.','..' +) { @a=stat($x); say Dumper(\@a) }" $VAR1 = [ 2, 0, 16895, 1, 0, 0, 2, 0, 1340557931, 1340557931, 1336337436, '', '' ]; $VAR1 = [ 2, 0, 16895, 1, 0, 0, 2, 0, 1340557931, 1340557931, 1336337436, '', '' ]; $VAR1 = [ 2, 0, 16749, 1, 0, 0, 2, 0, 1339842184, 1339842184, 1247541608, '', '' ]; C:\Users\alex>
Exact match for ".". Are quotes removed automatically?
C:\Users\alex>perl -MData::Dumper -E "@a=stat(chr(34).'Desktop'.chr(34 +)); say Dumper(\@a)" $VAR1 = []; C:\Users\alex>perl -MData::Dumper -E "@a=stat(''); say Dumper(\@a)" $VAR1 = []; C:\Users\alex>perl -MData::Dumper -E "@a=stat(chr(34).'..'.chr(34)); s +ay Dumper(\@a)" $VAR1 = []; C:\Users\alex>perl -MData::Dumper -E "@a=stat(chr(34).'.'.chr(34)); sa +y Dumper(\@a)" $VAR1 = []; C:\Users\alex>
No. I have no clue why '""' is treated like '.' on Windows.
What happens when I call stat() from C/MinGW?
#include <stdio.h> #include <sys/types.h> #include <sys/stat.h> #include <unistd.h> int main(int argc, char ** argv) { struct stat st; printf("stat(\"\") = %i\n",stat("\"\"",&st)); return 0; }
X:\>gcc -o stattest.exe stattest.c X:\>stattest stat("") = -1 X:\>
So, it's very likely neither Windows nor MinGW, so it must be Perl.
Alexander
In reply to Re: true from (-e "") on Windoze
by afoken
in thread true from (-e "") on Windoze
by CarolinaPerler
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