3 stable releases

2.0.0 Oct 24, 2022
1.0.1 Feb 24, 2022
1.0.0 Feb 2, 2022

#952 in Command line utilities

22 downloads per month

Custom license

377 lines


Reveals whomst thou art with a single character.


Available via the Anti-Capitalist Software License for individuals, non-profit organisations, and worker-owned businesses.


Just build omst and omst-be for your system and install them in /usr/bin.


omst prints one of five characters based upon your effective user permissions:

  1. # for absolute permissions (i.e. root, administrator)
  2. @ for system users
  3. $ for ordinary users
  4. % for restricted users (e.g. nobody, guest)
  5. ? if any error occurs

In all cases, the character is followed by a newline. If an error occurs, the exit status will be nonzero; to see full errors, run omst-be instead.

System support

Currently, unix-family systems (via libc & shadow) and Windows (via WinAPI) are supported. Android support is currently unavailable.

Mac OS and iOS are supported on a "coincidental" basis, meaning that if it happens to work under the existing code, nice! Otherwise, no substantial code will be added for these targets, since Apple does not make it easy to test software on their platforms without dedicated hardware.

Implementation specifics

Under unix-family systems, the permissions are mapped based upon the effective user ID (libc::getuid) and the UID_MIN and UID_MAX fields of /etc/login.defs:

  1. Absolute: UID 0 (usually, but not always the root user)
  2. System: Below UID_MIN
  3. User: Between UID_MIN and UID_MAX (inclusive)
  4. Guest: Above UID_MAX

Under Windows, the permissions are mapped based upon the priv field of the USER_INFO struct:

  1. Absolute: USER_PRIV_ADMIN
  2. System: Unused (Windows doesn't have system users)