How to name a file to be the very first in Nautilus?

The prefix 0 already makes the file to be sorted at very first in Nautilus. What can come before the very first file? No files could, except directories. This is true regardless of locale in use.

File naming

In the following example, I first created an empty text file named apple.txt then made multiple copies and rename each of the files by adding single character prefix. I have used only most compatible alphanumeric characters: 0 A á _ - and (space). This means I have created 7 files in total, plus a directory named apple for reference.

Note that á is the second letter of Czech, which is found in this article section on Wikipedia. The first letter seems to be same as English: A and a.

File sorting

How will Nautilus sort these files in different locale environment? Turns out that it is similar but slightly different. See the following screenshot for comparison.

Nautilus sorted files in English environment en_US.UTF-8 like this:

apple <-- directory
0apple.txt
Aapple.txt
áapple.txt
apple.txt <-- original file without prefix
 apple.txt
_apple.txt
-apple.txt

Nautilus sorted files in Czech environment cs_CZ.UTF-8 like this:

apple <-- directory
0apple.txt
Aapple.txt
áapple.txt
 apple.txt
apple.txt <-- original file without prefix
-apple.txt
_apple.txt

In both locales, there is no change in order of directory and top 3 files when viewing as list in Nautilus. This already shows that no alphanumeric character can appear before 0apple.txt.

Workaround 1

One way is to create files with name other than existing "apple" with same prefix 0 that precedes the existing one. Creating 0aaa.txt will come before 0apple.txt and so forth.

Using this workaround, the files are sorted like this:

0.txt
0a.txt
0aaa.txt
0apple.txt
...

This way, the file 0.txt would be the very first file to appear in Nautilus. No other files can come before 0.txt, unless user want to create a file name .txt (using only a space character).

Workaround 2

Say if apple is already the very first file that can exist and user insists to not rename apple, there is another way: Rename the existing file with higher number prefix from 0apple.txt to 9apple.txt. This will allow other files with lower number prefix 0* to 8* to appear before 9apple.txt.

Using this workaround, the files are sorted like this:

0mango.txt
1kiwi.txt
2orange.txt
...
9apple.txt
...

Workaround 2 is unsuitable, if the 0apple.txt as whole cannot be renamed for whatever reason. Workaround 1 will be more effective since 0.txt will always appear before 0mango.txt or other file names that user can think of.

How did I test

In my testing, only essential locale packages were installed to prepare Czech environment for running Nautilus in Ubuntu. The quick way to run program in other locale by LANG=<LOCALENAME> nautilus command didn't work. Hence, the following steps.

• Install these packages language-pack-gnome-cs language-pack-gnome-cs-base language-pack-cs language-pack-cs-base via APT in Terminal

• Go to System Settings > Language and Support

• In Language - Language for menus and windows, drag the entry named čeština (word for "Czech" noted by Wikipedia) to above English

• Log out and log in again to take effect

Tested using Nautilus 3.14.3 in Ubuntu 16.04 LTS (Live).

TL;DR Filename with prefix 0 makes the very first file in Nautilus. No other files, except directories can appear before the very first file.

Have you tried space zero as a prefix?

[ 0cat.py]

The other characters you mentioned does not work for me too but space zero works fine.

You can also try other combinations of spacial chars and zero, things like: -0cat.pay, _0cat.py, etc. these should work too.