But that said, using single back slashes in a C-string is a no-no, so you should at least double them up or use forward slashes.
Yeah, actually, I just quickly typed that part in by hand, I don't normally type out backslashes. I guess I should have copied/pasted code instead. 
My actual full save function is:
#SelectExpand
1// returns true if saved properly
2bool savemap
(ALLEGRO_DISPLAY *display, LEVEL
*level
)
3{
4 const char *filename
= NULL
;
5 ALLEGRO_FILECHOOSER *file_dialog
= NULL
;
6
7 /// TODO: Search folder for levels and set the filename to the next available level #
8 file_dialog
= al_create_native_file_dialog(".//",
"Save Level",
"*.dp2",
9 ALLEGRO_FILECHOOSER_SAVE
);
10 if(!file_dialog
) return false;
11
12 if(!al_show_native_file_dialog(display, file_dialog
)) {
13 if(file_dialog
) al_destroy_native_file_dialog(file_dialog
);
14 return false;
15 }
16
17 filename
= al_get_native_file_dialog_path(file_dialog,
0);
18
19 FILE
*file
= NULL
;
20
21 file
= fopen(filename,
"wb");
22
23 fwrite(level->map_id,
sizeof(char),
strlen(level->map_id
), file
);
24
25 fputc(level->map_ver, file
);
26 fputc(level->validated, file
);
27 fputc(level->line_set, file
);
28 fputc(level->player.x, file
);
29 fputc(level->player.y, file
);
30 for(int i
= 0; i
< 4; i
++) {
31 fputc(level->ghost
[i
].x, file
);
32 fputc(level->ghost
[i
].y, file
);
33 }
34 fputc(level->pickup.x, file
);
35 fputc(level->pickup.y, file
);
36 fputc(level->background, file
);
37 for(unsigned char y
= 0; y
< MAPY
; y
++) {
38 for(unsigned char x
= 0; x
< MAPX
; x
++) {
39 fputc(level->map
[y
][x
].tile, file
);
40 fputc(level->map
[y
][x
].is_pill, file
);
41 fputc(level->map
[y
][x
].is_powerpill, file
);
42 }
43 }
44 fwrite(&level->pills,
sizeof(unsigned short),
1, file
);
45
46 // never forget to close the file
47 fclose(file
);
48
49 if(file_dialog
) al_destroy_native_file_dialog(file_dialog
);
50
51 return true;
52}
Currently it just goes to the default local folder to save, works well. I was thinking of changing the ".//" part (I copied that from someone on here, seems to work) so that it uses the filename variable, one that would be passed to this function, and it would contain the full path to the last loaded level (or default level name, eventually the function will scan for the next best name if there are none yet) and then the dialog would show the filename in it.
I have seen this in programs like Winamp, if you save your playlist, at first you have to select a filename, but once it is selected the next time you save it, the filename is there already set. I don't know how they do it. I'll have to look around and see what I can come up with I guess. I just figured it wouldn't do any harm to ask.
This is the dialog that Winamp uses with the previously selected filename already in place. I'm not sure how to get the same thing up, I've not programmed the Windows API much, but I'll look into it.
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]]>