# Change tab length in xpce debugger **URL:** \ **Category:** Help!\ **Tags:** how-to\ **Created:** [January 29, 2022, 12:55pm UTC](https://swi-prolog.discourse.group/t/change-tab-length-in-xpce-debugger/4953 "2022-01-29T12:55:08Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![kowalsky](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/kowalsky/32/394_2.png) [@kowalsky](https://swi-prolog.discourse.group/u/kowalsky)\ **Post date:** [January 29, 2022, 12:55pm UTC](https://swi-prolog.discourse.group/t/change-tab-length-in-xpce-debugger/4953/1 "2022-01-29T12:55:08Z")
I’m using: SWI-Prolog version 8.4.0 for x86\_64-linux I want to change the tab length in SWO-prolog debugger version 2.0. By default, the tab length is 8 but would like it to be 4 (to match my text editor’s settings). p.s. I love the XPCE debugger. ---
**Author:** ![jan](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/jan/32/4_2.png) [@jan](https://swi-prolog.discourse.group/u/jan)\ **Post date:** [January 29, 2022, 2:13pm UTC](https://swi-prolog.discourse.group/t/change-tab-length-in-xpce-debugger/4953/2 "2022-01-29T14:13:00Z")
You can add this line to xpce’s `Defaults` file: ``` emacs_fundamental_mode.tab_width: 4 ``` The simplest way to find this file is by opening an editor, e.g., using `?- emacs.` and using the menu _Edit/Editor preferences_. First time it will copy a version from the installation that contains a lot of useful settings commented. ---
**Author:** ![kowalsky](https://yyz2.discourse-cdn.com/free1/user_avatar/swi-prolog.discourse.group/kowalsky/32/394_2.png) [@kowalsky](https://swi-prolog.discourse.group/u/kowalsky)\ **Post date:** [January 30, 2022, 12:54am UTC](https://swi-prolog.discourse.group/t/change-tab-length-in-xpce-debugger/4953/3 "2022-01-30T00:54:40Z")
Worked perfectly. Thank you!