A concurrent
functional language for large
industrial
real-time systems by Armstrong, Williams and
Virding of Ellemtel, Sweden.
Erlang is untyped. It has
pattern matching syntax,
recursion equations, explicit
concurrency, asynchronous message passing and is relatively free from side-effects.
It supports transparent cross-
platform distribution. It has
primitives for detecting run-time errors, real-time
garbage collection, modules, dynamic code replacement (change
code in a continuously running real-time system) and a
foreign language interface.
An unsupported free version is available (subject to a
non-commercial licence). Commercial versions with support are
available from Erlang Systems AB. An
interpreter in
SICStus Prolog and compilers in
C and Erlang are available
for several
Unix platforms.
Open Telecom Platform (OTP) is a set of libraries and
tools.
Commercial version - sales, support,
training, consultants.
Open-source version - downloads, user-contributed
software, mailing lists.
Training and consulting.
E-mail: <erlang@erix.ericsson.se>.
[Erlang - "Concurrent Programming in Erlang", J. Armstrong, M.
& Williams R. Virding, Prentice Hall, 1993. ISBN 13-285792-8.]
36
CCS per hour, or 1 call-second per second.
Erlang is a unit without dimension, accepted internationally
for measuring the traffic intensity. This unit is defined as
the aggregate of continuous occupation of a channel for one
hour (3600 seconds). An intensity of one Erlang means the
channel is continuously occupied.