System variables are built-in variables that Visual FoxPro creates and maintains automatically. They are PUBLIC by default, but you can declare them PRIVATE.
Important The functionality of many system variables has been replaced by new features in Visual FoxPro. For details, see the description for each system variable.
The following table lists the five types of Visual FoxPro system variables and their designation in expressions:
| Variable type | Description | Expression |
| C | Character | cExpression |
| D | Date | dExpression |
| L | Logical | lExpression |
| N | Numeric | nExpression |
| O | Object | oExpression |
The following table lists all system variables — their types and default values:
| Variable | Type | Default value |
| _ALIGNMENT | C | LEFT |
| _ASCIICOLS | N | 80 |
| _ASCIIROWS | N | 63 |
| _ASSIST | C | Empty string |
| _BEAUTIFY | C | Empty string |
| _BOX | L | .T. |
| _BROWSER | C | Browser.app |
| _BUILDER | C | Builder.app |
| _CALCMEM | N | 0.0 |
| _CALCVALUE | N | 0.0 |
| _CLIPTEXT | C | Empty string |
| _CONVERTER | C | Convert.app |
| _COVERAGE | C | Coverage.app |
| _CUROBJ | N | -1 |
| _DBLCLICK | N | 0.5 |
| _DIARYDATE | D | Current date |
| _DOS | L | .T. in FoxPro for MS-DOS |
| _FOXDOC | C | Empty string |
| _GALLERY | C | Gallery.app |
| _GENGRAPH | C | Empty string |
| _GENHTML | C | Genhtml.prg |
| _GENMENU | C | Genmenu.prg |
| _GENPD | C | Empty string |
| _GENSCRN | C | Genscrn.prg |
| _GENXTAB | C | Empty string |
| _GETEXPR | C | Empty string |
| _INCLUDE | C | Empty string |
| _INDENT | N | 0 |
| _LMARGIN | N | 0 |
| _MAC | L | .T. in Visual FoxPro for Macintosh |
| _MLINE | N | 0 |
| _PADVANCE | C | FORMFEED |
| _PAGENO | N | 1 |
| _PBPAGE | N | 1 |
| _PCOLNO | N | Current column |
| _PCOPIES | N | 1 |
| _PDRIVER | C | Empty string |
| _PDSETUP | C | Empty string |
| _PECODE | C | Empty string |
| _PEJECT | C | NONE |
| _PEPAGE | N | 32767 |
| _PLENGTH | N | 66 |
| _PLINENO | N | 0 |
| _PLOFFSET | N | 0 |
| _PPITCH | C | DEFAULT |
| _PQUALITY | L | .F. |
| _PRETEXT | C | Empty string |
| _PSCODE | C | Empty string |
| _PSPACING | N | 1 |
| _PWAIT | L | .F. |
| _RMARGIN | N | 80 |
| _RUNACTIVEDOC | C | Runactd.prg |
| _SCCTEXT | C | Scctext.prg |
| _SCREEN | O | FORM |
| _SHELL | C | Empty string |
| _SPELLCHK | C | Spellchk.app |
| _STARTUP | C | Empty string |
| _TABS | C | Empty string |
| _TALLY | N | 0 |
| _TEXT | C | –1 |
| _THROTTLE | N | 0 |
| _TRANSPORT | C | Empty string |
| _TRIGGERLEVEL | N | 0 |
| _UNIX | L | .T. in FoxPro for UNIX |
| _VFP | O | Microsoft Visual FoxPro Application 6.0 |
| _WINDOWS | L | .T. in Visual FoxPro for Windows |
| _WIZARD | C | Wizard.app |
| _WRAP | L | .F. |