The gdefaults2 file is usually located inside the .crossfire directory.
This file applies to the new gtk-2 client for crossfire,
The older gtk-1 client used the gdefaults file as configuration file.

This configuration file does not exist in a fresh installation of the client.
This file gets created by pressing the 'Save' button in the client configuration sub window
found under Menubar > Client > Configure .

At the top of the file one reads :

# crossfire-client-gtk2 automatically generates this file.
# Manual editing is allowed, but the client may be a bit
# finicky about the keys and values.  Comparisons are case
# sensitive.  'True' and 'False' are the proper case, but
# have been replaced with 1 and 0 respectively.

Where the part 'True' and 'False' are the proper case
once applied to the X11 cfclient configuration file defaults .

The code in function load_defaults() in file client/gtk-v2/src/config.c parses as follows :

        if (inbuf[0]=='#') continue;
        /* Skip any setting line that does not contain a colon character */
        if (!(cp=strchr(inbuf,':'))) continue;
        *cp='\0';
        cp+=2;      /* colon, space, then value */
 
        val = -1;
        if (isdigit(*cp)) val=atoi(cp);
        else if (!strcmp(cp,"True")) val = TRUE;
        else if (!strcmp(cp,"False")) val = FALSE;

Meaning, that lines starting with # are ignored,
lines need to contain a colon : or are ignored,
and may have any content, but digits *not* -1 ,
and still recognizes True or False in case sensitive string comparison.

See also the gtk-1 gdefaults configfile, since the gdefaults2 does not differ much.

• auto_apply_container: < 0 | 1 > Default: 1
• cacheimages: < 0 | 1 > Default: 0
• command_window: < 0 | 1 > Default: 10
• darkness: < 0 | 1 > Default: 1
• displaymode: < 0 | 1 | 2 > CFG_DM_PIXMAP , CFG_DM_SDL , CFG_DM_OPENGL
• download_all_images: < 0 | 1 > Default: 0
• echo_bindings: < 0 | 1 > Default: 0
• faceset: Default: (null)
• fasttcpsend: < 0 | 1 > Default: 1
• fog_of_war: < 0 | 1 > Default: 1
• foodbeep: < 0 | 1 > Default: 0
• grad_color_bars: < 0 | 1 > Default: 0
• iconscale: < > Default: 100
• lighting: < 0 | 1 > Default: 1
• map_height: < > Default: 25
• mapscale: < > Default: 100
• mapscroll: < 0 | 1 > Default: 1
• map_width: < > Default: 25
• message_timestamping: < 0 | 1 > Default: 0
• nosplash: < 0 | 1 > Default: 1
• popups: < 0 | 1 > Default: 0
• port: < > Default: 13327
• resistances: < > Default: 0
• server: < > Default: (null)
• show_grid: < 0 | 1 > Default: 0
• showicon: < 0 | 1 > Default: 0
• sign_popups: < 0 | 1 > Default: 1
• smoothing: < 0 | 1 > Default: 0
• sound: < 0 | 1 > Default: 1
• split: < 0 | 1 > Default: 0
• splitinfo: < 0 | 1 > Default: 0
• theme: < 0 | 1 > Default: Standard
• tooltips: < 0 | 1 > Default: 1
• trim_info_window: < 0 | 1 > Default: 0
• window_layout: < > Default: gtk-v1.glade

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