File test failed!

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Hi, All:

I want to test if a file exists or it is a link or not, the code is:
#!/usr/bin/perl -w

use strict;
use File::Basename;
use File::stat;
use Fcntl ':mode';

my $elfobj = $ARGV[0];

sub strtrim ()
{
#.....
}

sub copyfile ()
{
#.....
}

my @deps = `ldd $elfobj`;
foreach my $lib (@deps) {
chomp ($lib);
my ($dep,$path) = split ("=>", $lib);
##handle path, and it value is /lib64/ld-linux-x86-64.so.2, which
is a link file.
if (-e $path) {
print $path."\n";
}
}

But the highlighted code always return undef. When put the code outside
of the foreach, it ok. Any one encountered this situation?

--------------080100010103040506030506--

Re: File test failed!

On 2011-09-16 17:53, yyq@eisoo.com wrote:
> I want to test if a file exists or it is a link or not

You test for a regular file with -f.
You test for existance with -e.
You test for symbolic links with -l.

See
perldoc -f -x
for more information.

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â”=82 m@japh.se
â”=82 http://japh.se

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Re: File test failed!

Hi YYQ,

On Fri, 16 Sep 2011 17:53:25 +0800
"yyq@eisoo.com" wrote:

> Hi, All:
>=20
> I want to test if a file exists or it is a link or not, the code is:
> #!/usr/bin/perl -w
>=20
> use strict;
> use File::Basename;
> use File::stat;
> use Fcntl ':mode';
>=20
> my $elfobj =3D $ARGV[0];
>=20
> sub strtrim ()
> {
> #.....
> }
>=20
> sub copyfile ()
> {
> #.....
> }
>=20
> my @deps =3D `ldd $elfobj`;
> foreach my $lib (@deps) {
> chomp ($lib);
> my ($dep,$path) =3D split ("=3D>", $lib);
> ##handle path, and it value is /lib64/ld-linux-x86-64.so.2, which=20
> is a link file.
> if (-e $path) {
> print $path."\n";
> }
> }

Well, one problem I can see is that the ldd output contains whitespace befo=
re
and after the "=3D>", so this may trip you. To be sure what exactly is happ=
ening,
you can use the perl debugger ("perl -d") to investigate:

http://perl-begin.org/topics/debugging/

Regards,

Shlomi Fish

--=20
------------------------------------------------------------ -----
Shlomi Fish http://www.shlomifish.org/
First stop for Perl beginners - http://perl-begin.org/

In Soviet Russia, every time you kill a kitten, God masturbates.
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