Projects / FakeTime Preload Library (l...

FakeTime Preload Library (libfaketime)

FTPL (FakeTime Preload Library, aka libfaketime) intercepts various system library calls and tricks programs of your choice into seeing a faked system time without having to change the time system-wide. This can be used for running legacy software with Y2K bugs, testing software for year-2038 compliance, debugging time-related issues such as expired SSL certificates, and using software that ceases to run outside a certain time frame. The faked time can be specified either absolutely or relative to the real current time, and optionally also affects file timestamps. The faked clock continues to run, but can optionally be frozen, slowed down, or made faster. A wrapper script "faketime" simplifies the usage, similar to tools such as fakechroot.

Operating Systems

RSS Recent releases

  •  13 Oct 2013 22:59

Release Notes: New features: support for nanosecond resolution, saving timestamps to files, speeding up/slowing down per-process timers, and faking system calls such as sleep() and alarm(). Adds an option to use the same global clock setting for all libfaketime-spawned processes. Support for advancing the time with each time-related system call ("deterministic time"). A new "timeprivacy" wrapper ensures that programs are started with unique timestamps. Fixes: significantly improved support for OSX; fixed support for recent glibc versions; and improved compatibility with multiarch/multilib Linux systems.

  •  21 Jan 2012 20:07

Release Notes: This release fixes packaging.

  •  12 Jan 2012 22:05

Release Notes: This release adds improved support for Mac OS X 10.7 (Lion). It also provides several new features on all supported operating systems to limit libfaketime's activities, e.g., to only a certain time interval; and to execute external programs, e.g., shell scripts, at a specified point during run-time.

  •  22 May 2011 09:14

Release Notes: This is a maintenance release. Changes were made to directory structure and deployment routines.

  •  24 Aug 2008 21:43

Release Notes: This version adds support to speed up/slow down the system clock, intercepts calls to the new system functions fstatat() and fstatat64(), allows fractional values for offset specification, and comes with a new wrapper script and a man page for eased system-wide installation and use.


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