/usr/lib/swi-prolog/xpce/bitmaps/cross.bm is in swi-prolog-x 6.6.4-2ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | #define cross.bm_width 16
#define cross.bm_height 16
static char cross.bm_bits[] = {
0x80, 0x01, 0x80, 0x01, 0x80, 0x01, 0x80, 0x01, 0x90, 0x09, 0xa0, 0x05,
0xc0, 0x03, 0x7f, 0xfe, 0x7f, 0xfe, 0xc0, 0x03, 0xa0, 0x05, 0x90, 0x09,
0x80, 0x01, 0x80, 0x01, 0x80, 0x01, 0x80, 0x01};
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