Precise POSIX clock for OCaml
Mickaël Delahaye, http://micdel.fr
This module provides access to precise time information (in nanoseconds) on
POSIX-compatible system (Linux, FreeBSD, OpenBSD, etc.). It is made possible
through the clock_gettime (2)
family of functions. Through times are
given in nanoseconds, their actual accuracies greatly vary depending on the
system.
Easy install (with OPAM)
opam update
opam install oclock
Done.
Just the usual suspects: GNU Make, GCC, OCaml, and optionally Findlib (i.e., ocamlfind).
Also, a true POSIX system, i.e., not MacOS. Indeed MacOS does not support
clock_gettime
. There are alternatives but I do not have a Mac... if you are
interested in extending the library, let me know.
make
Build the library.
make install
Install the library in the standard ocaml directory. Depending on your
configuration you may have to sudo
the last command or to run it as root.
Manually:
ocamlc -I +oclock oclock.cma ...
ocamlopt -I +oclock oclock.cmxa ...
Or with ocamlfind:
ocamlfind ocamlc -package oclock ...
ocamlfind ocamlopt -package oclock ...
The main source of information is the Oclock API documentation available online. It can be build locally as follows:
make doc
Then, open doc/index.html
with your favorite browser.
Available clocks differ under the various POSIX systems (e.g., see Linux, OpenBSD, and FreeBSD man-pages). Most differences between systems are levelled out by the OCaml interface.
Two examples are also provided in the examples
directory:
getcputime
gets the CPU-time consumed by a process given its PID.realtime
gets the real time since the Epoch, and evaluates the clock precision inside OCaml.
Copyright (c) 2011-2013, Mickaël Delahaye, http://micdel.fr
Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.