File::stat - by-name interface to Perl's built-in stat() functions
use File::stat;
$st = stat($file) or die "No $file: $!";
if ( ($st->mode & 0111) && $st->nlink > 1) ) {
print "$file is executable with lotsa links\n";
}
if ( -x $st ) {
print "$file is executable\n";
}
use Fcntl "S_IRUSR";
if ( $st->cando(S_IRUSR, 1) ) {
print "My effective uid can read $file\n";
}
use File::stat qw(:FIELDS);
stat($file) or die "No $file: $!";
if ( ($st_mode & 0111) && ($st_nlink > 1) ) {
print "$file is executable with lotsa links\n";
}
This module's default exports override the core stat()
and lstat() functions, replacing them with versions that return
``File::stat'' objects. This object has methods that
return the similarly named structure field name from the
stat(2) function; namely,
dev,
ino,
mode,
nlink,
uid,
gid,
rdev,
size,
atime,
mtime,
ctime,
blksize,
and
blocks.
As of version 1.02 (provided with perl 5.12) the object provides "-X"
overloading, so you can call filetest operators (-f , -x , and so
on) on it. It also provides a ->cando method, called like
$st->cando( ACCESS, EFFECTIVE )
where ACCESS is one of S_IRUSR , S_IWUSR or S_IXUSR from the
Fcntl module, and EFFECTIVE indicates whether to use
effective (true) or real (false) ids. The method interprets the mode ,
uid and gid fields, and returns whether or not the current process
would be allowed the specified access.
If you don't want to use the objects, you may import the ->cando
method into your namespace as a regular function called stat_cando .
This takes an arrayref containing the return values of stat or
lstat as its first argument, and interprets it for you.
You may also import all the structure fields directly into your namespace
as regular variables using the :FIELDS import tag. (Note that this still
overrides your stat() and lstat() functions.) Access these fields as
variables named with a preceding st_ in front their method names.
Thus, $stat_obj->dev() corresponds to $st_dev if you import
the fields.
To access this functionality without the core overrides,
pass the use an empty import list, and then access
function functions with their full qualified names.
On the other hand, the built-ins are still available
via the CORE:: pseudo-package.
As of Perl 5.8.0 after using this module you cannot use the implicit
$_ or the special filehandle _ with stat() or lstat(), trying
to do so leads into strange errors. The workaround is for $_ to
be explicit
my $stat_obj = stat $_;
and for _ to explicitly populate the object using the unexported
and undocumented populate() function with CORE::stat():
my $stat_obj = File::stat::populate(CORE::stat(_));
- -%s is not implemented on a File::stat object
-
The filetest operators
-t , -T and -B are not implemented, as
they require more information than just a stat buffer.
These can all be disabled with
no warnings "File::stat";
- File::stat ignores use filetest 'access'
-
You have tried to use one of the
-rwxRWX filetests with use
filetest 'access' in effect. File::stat will ignore the pragma, and
just use the information in the mode member as usual.
- File::stat ignores VMS ACLs
-
VMS systems have a permissions structure that cannot be completely
represented in a stat buffer, and unlike on other systems the builtin
filetest operators respect this. The
File::stat overloads, however,
do not, since the information required is not available.
While this class is currently implemented using the Class::Struct
module to build a struct-like class, you shouldn't rely upon this.
Tom Christiansen
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