| Item | Description |
| CSetCent() | Queries or changes the SET CENTURY setting. |
| CSetCurs() | Queries or changes the SET CURSOR setting. |
| CSetKey() | Retrieves the code block associated with a key. |
| DosParam() | Returns the command line parameters passed to an xHarbour application. |
| ExeName() | Returns the EXE file name of an xHarbour application. |
| GetE() | Retrieves an operating system environment variable. |
| GetEnv() | Retrieves an operating system environment variable. |
| HB_AParams() | Collects values of all parameters passed to a function, method or procedure. |
| HB_ArgC() | Returns the number of command line arguments. |
| HB_ArgCheck() | Checks if an internal switch is set on the command line. |
| HB_ArgString() | Retrieves the vale of an internal switch set on the command line. |
| HB_ArgV() | Retrieves the value of a command line argument. |
| HB_BuildDate() | Retrieves the formatted build date of the xHarbour compiler |
| HB_BuildInfo() | Retrieves build information of the xHarbour compiler. |
| HB_CmdArgArgV() | Returns the first command line argument (EXE file name). |
| HB_Compiler() | Retrieves the version of the C compiler shipped with xHarbour. |
| HB_EnumIndex() | Returns the current ordinal position of a FOR EACH iteration. |
| HB_GCAll() | Scans the memory and releases all garbage memory blocks. |
| HB_GCStep() | Invokes the garbage collector for one collection cycle. |
| HB_OsDriveSeparator() | Returns the operating specific drive separator character. |
| HB_OsNewLine() | Returns the end-of-line character(s) to use with the current operating system. |
| HB_OsPathDelimiters() | Returns the operating specific characters for paths. |
| HB_OsPathListSeparator() | Returns the operating specific separator character for a path list. |
| HB_OsPathSeparator() | Returns the operating specific separator character for a path. |
| HB_PCodeVer() | Retrieves the PCode version of the current xHarbour build. |
| HB_SetKeyArray() | Associates a code block with multiple keys. |
| HB_SetKeyCheck() | Evaluates a code block associated with a key. |
| HB_SetKeyGet() | Retrieves code blocks associated with a key. |
| HB_SetKeySave() | Queries or changes all SetKey() code blocks. |
| HB_VMMode() | Indicates the creation mode of the xHarbour virtual machine. |
| Memory() | Returns memory statistics. |
| NetName() | Retrieves the current user name or the computer name. |
| Os() | Returns the name of the operating system. |
| Os_IsWin2000() | Checks if the application is running on Windows 2000. |
| Os_IsWin2000_Or_Later() | Checks if the application is running on Windows version 2000 or later |
| Os_IsWin2003() | Checks if the application is running on Windows 2003. |
| Os_IsWin95() | Checks if the application is running on Windows 95. |
| Os_IsWin98() | Checks if the application is running on Windows 98. |
| Os_IsWin9X() | Checks if the application is running on a Windows 9x platform. |
| Os_IsWinME() | Checks if the application is running on Windows ME. |
| Os_IsWinNT() | Checks if the application is running on a Windows NT platform. |
| Os_IsWinNT351() | Checks if the application is running on Windows NT 3.51. |
| Os_IsWinNT4() | Checks if the application is running on Windows NT 4.0. |
| Os_IsWinVista() | Checks if the application is running on Windows Vista. |
| Os_IsWinXP() | Checks if the application is running on Windows XP. |
| Os_IsWtsClient() | Checks if the application is running on a Windows Terminal Server client. |
| Os_VersionInfo() | Retrieves specific version information about the operating system. |
| PCol() | Returns the column position of the print head. |
| PCount() | Returns the number of passed parameters. |
| PRow() | Returns the row position of the print head. |
| PValue() | Retrieves the value of a parameter passed to a function, method or procedure. |
| Set() | Retrieves or changes a system setting. |
| SetCancel() | Determines if Alt+C and Ctrl+Break terminate an application |
| SetDate() | Changes the system date from a Date value. |
| SetKey() | Associates a code block with a key. |
| SetPrc() | Changes the PRow() and PCol() values. |
| Tone() | Sounds a speaker tone with specific tone frequency and duration. |
| Used() | Determines if a database file is open in a work area. |
| Version() | Retrieves xHarbour version information. |
