A Python module to customize the process title

.. image:: https://github.com/dvarrazzo/py-setproctitle/workflows/Tests/badge.svg :target: https://github.com/dvarrazzo/py-setproctitle/actions?query=workflow%3ATests :alt: Tests

:author: Daniele Varrazzo

The setproctitle module allows a process to change its title (as displayed by system tools such as ps, top or MacOS Activity Monitor).

Changing the title is mostly useful in multi-process systems, for example when a master process is forked: changing the children's title allows to identify the task each process is busy with. The technique is used by PostgreSQL_ and the OpenSSH Server_ for example.

The procedure is hardly portable across different systems. PostgreSQL provides a good multi-platform implementation__: this package was born as a wrapper around PostgreSQL code.

• Homepage <https://github.com/dvarrazzo/py-setproctitle>__
• Download <http://pypi.python.org/pypi/setproctitle/>__
• Bug tracker <https://github.com/dvarrazzo/py-setproctitle/issues>__

.. _PostgreSQL: http://www.postgresql.org .. _OpenSSH Server: http://www.openssh.com/ .. __: http://doxygen.postgresql.org/ps__status_8c_source.html

Installation

setproctitle is a C extension: in order to build it you will need a C compiler and the Python development support (the python-dev or python3-dev package in most Linux distributions). No further external dependencies are required.

You can use pip to install the module::

pip install setproctitle

You can use pip -t or virtualenv for local installations, sudo pip for a system-wide one... the usual stuff. Read pip_ or virtualenv_ docs for all the details.

.. _pip: https://pip.readthedocs.org/ .. _virtualenv: https://virtualenv.readthedocs.org/

Usage

.. note:: You should import and use the module (even just calling getproctitle()) pretty early in your program lifetime: code writing env vars may interfere__ with the module initialisation.

.. __: https://github.com/dvarrazzo/py-setproctitle/issues/42

The setproctitle module exports the following functions:

setproctitle(title) Set title as the title for the current process.

getproctitle() Return the current process title.

The process title is usually visible in files such as /proc/PID/cmdline, /proc/PID/status, /proc/PID/comm, depending on the operating system and kernel version. These information are used by user-space tools such as ps and top.

setthreadtitle(title) Set title as the title for the current thread.

getthreadtitle() Get the current thread title.

The thread title is exposed by some operating systems as the file /proc/PID/task/TID/comm, which is used by certain tools such as htop.

Environment variables

A few environment variables can be used to customize the module behavior:

``SPT_NOENV``
    Avoid clobbering ``/proc/PID/environ``.

    On many platforms, setting the process title will clobber the
    ``environ`` memory area. ``os.environ`` will work as expected from within
    the Python process, but the content of the file ``/proc/PID/environ`` will
    be overwritten.  If you require this file not to be broken you can set the
    ``SPT_NOENV`` environment variable to any non-empty value: in this case
    the maximum length for the title will be limited to the length of the
    command line.

``SPT_DEBUG``
    Print debug information on ``stderr``.

    If the module doesn't work as expected you can set this variable to a
    non-empty value to generate information useful for debugging.  Note that
    the most useful information is printed when the module is imported, not
    when the functions are called.


Module status
-------------

The module can be currently compiled and effectively used on the following
platforms:

- GNU/Linux
- BSD
- MacOS X
- Windows

Note that on Windows there is no way to change the process string:
what the module does is to create a *Named Object* whose value can be read
using a tool such as `Process Explorer`_ (contribution of a more useful tool
to be used together with ``setproctitle`` would be well accepted).

The module can probably work on HP-UX, but I haven't found any to test with.
It is unlikely that it can work on Solaris instead.

.. _Process Explorer: http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx

Releases history
----------------

Version 1.3.7
-------------

- Add support for Python 3.14 (issue #152).


Version 1.3.6
-------------

- Add support for free-threading (issue #147).


Version 1.3.5
-------------

- Fix bouncing Dock icon on macOS (issue #143).
- Fix building on C23 compilers (issue #145).


Version 1.3.4
-------------

- Add support for Python 3.13 (issue #139).
- Drop support for Python 3.7.


Version 1.3.3
-------------

- Add support for Python 3.12.
- Fix package metadata to include Python 3.11, 3.12.


Version 1.3.2
-------------

- Restore import-time initialization of macOS to avoid crash on thread+fork
  (issue #113).


Version 1.3.1
-------------

- Fixed segfault on macOS 12.5 in forked processes (issue #111).
  Note that, as a workaround, Activity Monitor will show the title of the
  parent.


Version 1.3.0
-------------

- Added fallback no-op implementation if building the extension fails.
- Added support for displaying title as the process name in MacOS Activity
  Monitor (issue #10).
- Fixed "Symbol not found: _Py_GetArgcArgv" error when using Xcode provided
  Python (issues #82, #103).
- Fixed FreeBSD support, broken in 1.2 (issue #94).
- Added package type annotations (issue #101).
- Dropped support for Python 3.6.


Version 1.2.3
-------------

- Added Python 3.10 packages (issue #102).
- Added Wheel packages for macOS (issue #96).
- Package build moved to cibuildwheel, other wheels provided (issue #47).


Version 1.2.2
-------------

- Fixed Windows build (issues #89, #90).
- Added wheel packages for Windows (issues #47, #90).
- Added wheel packages for aarch64 (issue #95).


Version 1.2.1
-------------

- Fixed segfault after ``os.environ.clear()`` (issue #88).


Version 1.2
~~~~~~~~~~~

- added ``getthreadtitle()`` and ``setthreadtitle()``.
- Initialisation of the module moved to the first usage: importing the module
  doesn't cause side effects.
- Manage much longer command lines (issue #52)
- Improved build on BSD, dropped ancient versions (issue #67).
- Fixed build for Python 3.8 (issues #66, #72)
- Added support for Python 3.9
- Dropped support for Python < 3.6


Version 1.1.10
~~~~~~~~~~~~~~

- Fixed building with certain ``prctl.h`` implementations (issue #44).
- Use ``setuptools`` if available (issue #48).


Version 1.1.9
~~~~~~~~~~~~~

- Fixed build on VC (issues #20, #33).
- Added ``MANIFEST.in`` to the source distribution to help with RPM building
  (issue #30).


Version 1.1.8
~~~~~~~~~~~~~

- Added support for Python "diehard" 2.4 (pull request #3).
- Fixed build on Mac OS X 10.9 Maverick (issue #27).


Version 1.1.7
~~~~~~~~~~~~~

- Added PyPy support, courtesy of Ozan Turksever - http://www.logsign.net
  (pull request #2).


Version 1.1.6
~~~~~~~~~~~~~

- The module can be compiled again on Windows (issue #21).


Version 1.1.5
~~~~~~~~~~~~~

- No module bug, but a packaging issue: files ``README`` and ``HISTORY``
  added back into the distribution.


Version 1.1.4
~~~~~~~~~~~~~

- The module works correctly in embedded Python.
- ``setproctitle()`` accepts a keyword argument.
- Debug output support always compiled in: the variable ``SPT_DEBUG`` can be
  used to emit debug log.


Version 1.1.3
~~~~~~~~~~~~~

- Don't clobber environ if the variable ``SPT_NOENV`` is set (issue #16).


Version 1.1.2
~~~~~~~~~~~~~

- Find the setproctitle include file on OpenBSD (issue #11).
- Skip test with unicode if the file system encoding wouldn't make it pass
  (issue #13).


Version 1.1.1
~~~~~~~~~~~~~

- Fixed segfault when the module is imported under mod_wsgi (issue #9).


Version 1.1
~~~~~~~~~~~

- The module works correctly with Python 3.


Version 1.0.1
~~~~~~~~~~~~~

- ``setproctitle()`` works even when Python messes up with argv, e.g. when run
  with the -m option (issue #8).


Version 1.0
~~~~~~~~~~~

No major change since the previous version.  The module has been heavily used
in production environment without any problem reported, so it's time to declare
it stable.


Version 0.4
~~~~~~~~~~~

- Module works on BSD (tested on FreeBSD 7.2).

- Module works on Windows. Many thanks to `Develer`_ for providing a neat `GCC
  package for Windows with Python integration`__ that made the Windows porting
  painless.

  .. _Develer: http://www.develer.com/
  .. __: http://www.develer.com/oss/GccWinBinaries


Version 0.3
~~~~~~~~~~~

- Module works on Mac OS X 10.2. Reported working on OS X 10.6 too.


Version 0.2
~~~~~~~~~~~

- Added ``prctl()`` call on Linux >= 2.6.9 to update ``/proc/self/status``.


Version 0.1
~~~~~~~~~~~

- Initial public release.