DBD::WMI - interface to the Windows WMI
This module allows you to issue WQL queries through the DBI.
use DBI;
my $dbh = DBI->connect('dbi:WMI:');
my $sth = $dbh->prepare(<<WQL);
SELECT * FROM Win32_Process
WQL
$sth->execute();
while (my @row = $sth->fetchrow) {
my $proc = $row[0];
print join "\t", $proc->{Caption}, $proc->{ExecutablePath} || "<system>";
# $proc->Terminate();
print "\n";
}
The WMI allows you to query various tables ("namespaces"), like the filesystem, currently active processes and events:
SELECT * FROM Win32_Process
The driver/WMI implements two kinds of queries, finite queries like the query above and potentially infinite queries for events as they occur in the system:
my $query = q{
SELECT * FROM __instanceoperationevent
WITHIN 1
WHERE TargetInstance ISA 'Win32_DiskDrive'
}
This query returns one row (via ->fetchrow_arrayref() ) whenever a disk drive gets added to or removed from the system (think of an USB stick).
There is currently no support for selecting specific
columns instead of *
. Support for selecting columns that
then get returned as plain Perl scalars is planned.
This routine parses out the requested columns from the WQL statement and returns an array reference with the names of the columns.
Currently, this only works for SELECT
statements.
All other statements get an implicit column
of *
, meaning that the Win32::OLE objects
will be returned.
The WMI and WQL return full objects instead of single columns. The specification
of columns is merely a hint to the object what properties to preload. The
DBD interface deviates from that approach in that it returns objects
for queries of the form SELECT *
and the values of the object
properties when columns are specified. These columns are then case sensitive.
SELECT * FROM Win32_Printer
SELECT * FROM Win32_PrintJob
WHERE DriverName = 'HP Deskjet 6122'
SELECT * FROM __InstanceCreationEvent
WITHIN 10
WHERE
TargetInstance ISA 'Win32_PrintJob'
SELECT * FROM Win32_Printer
WHERE Default = TRUE
use DBI;
my $dbh = DBI->connect('dbi:WMI:');
my $sth = $dbh->prepare(<<WQL);
SELECT * FROM Win32_Printer
WQL
$sth->execute;
while (my @row = $sth->fetchrow) {
# We get Win32::OLE objects back:
my $printer = $row[0];
printf "Making %s the default printer\n", $printer->{Name};
$printer->SetDefaultPrinter;
};
SELECT * from Win32_NetworkAdapterConfiguration
WHERE IPEnabled = True
ASSOCIATORS OF {Win32_Directory.Name='C:\WINNT'}
WHERE ResultClass = CIM_DataFile
use DBI;
my $machine = 'dawn';
my $dbh = DBI->connect('dbi:WMI:'.$machine);
my $sth = $dbh->prepare(<<WQL);
SELECT * FROM Win32_Printer
WQL
$sth->execute;
while (my @row = $sth->fetchrow) {
my $printer = $row[0];
printf "Making %s the default printer on %s\n", $printer->{Name}, $machine;
$printer->SetDefaultPrinter;
};
use Win32::OLE qw(in);
...
SELECT * FROM Win32_Process
$sth->execute;
while (my @row = $sth->fetchrow) {
for my $method (in $row[0]->Methods_) {
print "Can call $method() on the object\n"
};
};
- Implement placeholders and proper interpolation of values
- Need to implement DSN parameters for remote computers, credentials
WMI is Microsofts implementation of the WBEM standard (http://www.dmtf.org/standards/wbem/) except that it uses DCOM and not CIM-XML as the transport medium.
The MS WMI main page at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmisdk/wmi/wmi_start_page.asp
The WQL documentation at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmisdk/wmi/wql_sql_for_wmi.asp
The "Hey Scripting Guy" column at http://www.microsoft.com/technet/scriptcenter/resources/qanda/default.mspx
Wikipedia on WMI at http://en.wikipedia.org/wiki/Windows_Management_Instrumentation
List of available Win32 WMI classes at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmisdk/wmi/win32_classes.asp
The public repository of this module is https://github.com/Corion/dbd-wmi.
The public support forum of this module is https://perlmonks.org/.
Please report bugs in this module via the RT CPAN bug queue at https://rt.cpan.org/Public/Dist/Display.html?Name=DBD-WMI or via mail to [email protected].
Max Maischein [email protected]
Copyright 2009-2018 by Max Maischein [email protected]
.
This module is released under the same terms as Perl itself.