Accessing the Windows File System from SQL Server

sample.sql

--Extended Stored Procedure - xp_cmdshell - Ability to execute any DOS command line code.
EXEC master.dbo.xp_cmdshell 'dir c:\'
GO 

--Extended Stored Procedure - xp_fixeddrives - Ability to capture the free drive space in megabytes.
EXEC master.dbo.xp_fixeddrives
GO 
--Extended Stored Procedure - xp_subdirs - Ability to capture the sub directories, but not files
EXEC master.dbo.xp_subdirs 'c:\'
GO