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.\" -*- mode: troff; coding: utf-8 -*-
.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43)
.\"
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.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
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.\" ========================================================================
.\"
.IX Title "File::stat 3perl"
.TH File::stat 3perl 2024-05-30 "perl v5.38.2" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
File::stat \- by\-name interface to Perl's built\-in stat() functions
.SH SYNOPSIS
.IX Header "SYNOPSIS"
.Vb 5
\& use File::stat;
\& my $st = stat($file) or die "No $file: $!";
\& if ( ($st\->mode & 0111) && ($st\->nlink > 1) ) {
\&     print "$file is executable with lotsa links\en";
\& } 
\&
\& if ( \-x $st ) {
\&     print "$file is executable\en";
\& }
\&
\& use Fcntl "S_IRUSR";
\& if ( $st\->cando(S_IRUSR, 1) ) {
\&     print "My effective uid can read $file\en";
\& }
\&
\& use File::stat qw(:FIELDS);
\& stat($file) or die "No $file: $!";
\& if ( ($st_mode & 0111) && ($st_nlink > 1) ) {
\&     print "$file is executable with lotsa links\en";
\& }
.Ve
.SH DESCRIPTION
.IX Header "DESCRIPTION"
This module's default exports override the core \fBstat()\fR 
and \fBlstat()\fR functions, replacing them with versions that return 
"File::stat" objects.  This object has methods that
return the similarly named structure field name from the
\&\fBstat\fR\|(2) function; namely,
dev,
ino,
mode,
nlink,
uid,
gid,
rdev,
size,
atime,
mtime,
ctime,
blksize,
and
blocks.
.PP
As of version 1.02 (provided with perl 5.12) the object provides \f(CW"\-X"\fR
overloading, so you can call filetest operators (\f(CW\*(C`\-f\*(C'\fR, \f(CW\*(C`\-x\*(C'\fR, and so
on) on it. It also provides a \f(CW\*(C`\->cando\*(C'\fR method, called like
.PP
.Vb 1
\& $st\->cando( ACCESS, EFFECTIVE )
.Ve
.PP
where \fIACCESS\fR is one of \f(CW\*(C`S_IRUSR\*(C'\fR, \f(CW\*(C`S_IWUSR\*(C'\fR or \f(CW\*(C`S_IXUSR\*(C'\fR from the
Fcntl module, and \fIEFFECTIVE\fR indicates whether to use
effective (true) or real (false) ids. The method interprets the \f(CW\*(C`mode\*(C'\fR,
\&\f(CW\*(C`uid\*(C'\fR and \f(CW\*(C`gid\*(C'\fR fields, and returns whether or not the current process
would be allowed the specified access.
.PP
If you don't want to use the objects, you may import the \f(CW\*(C`\->cando\*(C'\fR
method into your namespace as a regular function called \f(CW\*(C`stat_cando\*(C'\fR.
This takes an arrayref containing the return values of \f(CW\*(C`stat\*(C'\fR or
\&\f(CW\*(C`lstat\*(C'\fR as its first argument, and interprets it for you.
.PP
You may also import all the structure fields directly into your namespace
as regular variables using the :FIELDS import tag.  (Note that this still
overrides your \fBstat()\fR and \fBlstat()\fR functions.)  Access these fields as
variables named with a preceding \f(CW\*(C`st_\*(C'\fR in front their method names.
Thus, \f(CW\*(C`$stat_obj\->dev()\*(C'\fR corresponds to \f(CW$st_dev\fR if you import
the fields.
.PP
To access this functionality without the core overrides,
pass the \f(CW\*(C`use\*(C'\fR an empty import list, and then access
function functions with their full qualified names.
On the other hand, the built-ins are still available
via the \f(CW\*(C`CORE::\*(C'\fR pseudo-package.
.SH BUGS
.IX Header "BUGS"
As of Perl 5.8.0 after using this module you cannot use the implicit
\&\f(CW$_\fR or the special filehandle \f(CW\*(C`_\*(C'\fR with \fBstat()\fR or \fBlstat()\fR, trying
to do so leads into strange errors.  The workaround is for \f(CW$_\fR to
be explicit
.PP
.Vb 1
\&    my $stat_obj = stat $_;
.Ve
.PP
and for \f(CW\*(C`_\*(C'\fR to explicitly populate the object using the unexported
and undocumented \fBpopulate()\fR function with \fBCORE::stat()\fR:
.PP
.Vb 1
\&    my $stat_obj = File::stat::populate(CORE::stat(_));
.Ve
.SH ERRORS
.IX Header "ERRORS"
.IP "\-%s is not implemented on a File::stat object" 4
.IX Item "-%s is not implemented on a File::stat object"
The filetest operators \f(CW\*(C`\-t\*(C'\fR, \f(CW\*(C`\-T\*(C'\fR and \f(CW\*(C`\-B\*(C'\fR are not implemented, as
they require more information than just a stat buffer.
.SH WARNINGS
.IX Header "WARNINGS"
These can all be disabled with
.PP
.Vb 1
\&    no warnings "File::stat";
.Ve
.IP "File::stat ignores use filetest 'access'" 4
.IX Item "File::stat ignores use filetest 'access'"
You have tried to use one of the \f(CW\*(C`\-rwxRWX\*(C'\fR filetests with \f(CW\*(C`use
filetest \*(Aqaccess\*(Aq\*(C'\fR in effect. \f(CW\*(C`File::stat\*(C'\fR will ignore the pragma, and
just use the information in the \f(CW\*(C`mode\*(C'\fR member as usual.
.IP "File::stat ignores VMS ACLs" 4
.IX Item "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 \f(CW\*(C`File::stat\*(C'\fR overloads, however,
do not, since the information required is not available.
.SH NOTE
.IX Header "NOTE"
While this class is currently implemented using the Class::Struct
module to build a struct-like class, you shouldn't rely upon this.
.SH AUTHOR
.IX Header "AUTHOR"
Tom Christiansen