l+, l- (Set Source Options)

The l+and l- commands set the source line options that control source display and program stepping options.



+ or -
Specifies whether a given option is to be turned on (plus sign [+])or turned off (minus sign [-]).


One of the following options. The options must be in lowercase letters.


Displays source line numbers at the command prompt. You can disable source line display through l-ls or .prompt_allow -src. To make the source line numbers visible, you must enable source line display through both mechanisms.


Hides all messages (other than the source line and line number) when you are stepping through code. (The s option must also be active for the o option to have any effect.)

Displays source lines and source line numbers at the command prompt.


Starts source mode. If this mode is not set, the debugger is in assembly mode.

Turns on or turns off all options.


Item Description
Modes User mode, kernel mode
Targets Live, crash dump
Platforms All

Additional Information

For more information about source debugging and related commands, see Debugging in Source Mode. For more information about assembly debugging and related commands, see Debugging in Assembly Mode.


If you omit Option, the previously set options are displayed. In this case, the l+ and l- commands have identical effects. However, you must include a plus sign (+) or minus sign (-) for the l command to work.

You can include only one Option every time that you issue this command. If you list more than one option, only the first option is detected. However, by repeatedly issuing this command, you can turn on or off as many options as you want. (In other words, l+lst does not work, but l+l; l+s; l+t does achieve the effect that you want.)

When you specify the s option, source lines and line numbers are displayed when you step through code, regardless of whether you specified the l option. The o option has no effect unless you specify the s option.

Source line options do not take effect unless you enable line number loading by using the .lines (Toggle Source Line Support) command or the -lines command-line option. By default, if you have not used these commands, WinDbg turns on source line support and CDB turns it off.