I had this same problem today. There were no cookie or firewall problems and windows reported that the service was running successfully. This is what finally fixed it: Run RabbitMQ sbin command prompt as administrator. Run “rabbitmq-service remove” Run “rabbitmq-service install” For some reason the service set up by the installer did not configure several … Read more
String is not a data type in Erlang, it’s just a list of integers. But Erlang shell try to display lists as strings if possible: 1> S = [65, 66, 67, 68, 69, 70]. “ABCDEF” 2> S = “ABCDEF”. “ABCDEF” 3> io:write(S). [65,66,67,68,69,70]ok 4> [65, 66]. “AB” 5> [65, 66, 1]. [65,66,1]
The Erlang VM runs as one OS process. By default it runs one OS thread per core to achieve maximum utilisation of the machine. The number of threads and on which cores they run can be set when the VM is started. Erlang processes are implemented entirely by the Erlang VM and have no connection … Read more
Repeat after me: “These are different paradigms” Say that aloud 20 times or so — it is our mantra for the moment. If we really must compare apples and oranges, let’s at least consider where the common aspects of “being fruit” intersect. Java “objects” are a Java programmer’s basic unit of computation. That is, an … Read more
I think @Vijay’s answer is the best one so far and I just intend to Erlangify it. Pairs (cons cells) in Erlang are written as [Head|Tail] and nil is written as []. There is no restriction as to what the head and tail are but if you use the tail to chain more cons cells … Read more
I think your client is faulty because it specifies: {packet, 2} yet the server specifies (in code not shown) : {packet, 0} In Programming Erlang (2nd) on p. 269 it says: Note that the arguments to packet used by the client and the server must agree. If the server was opened with {packet,2} and the … Read more
Answer depends on the VM which is used: 1) non-SMP: There is one scheduler (OS thread), which executes all Erlang processes, taken from the pool of runnable processes (i.e. those who are not blocked by e.g. receive) 2) SMP: There are K schedulers (OS threads, K is usually a number of CPU cores), which executes … Read more
Printed process ids < A.B.C > are composed of 6: A, the node number (0 is the local node, an arbitrary number for a remote node) B, the first 15 bits of the process number (an index into the process table) 7 C, bits 16-18 of the process number (the same process number as B) … Read more
Just to clarify the naming, they are both functions. One is a named function and the other is an anonymous one. But you are right, they work somewhat differently and I am going to illustrate why they work like that. Let’s start with the second, fn. fn is a closure, similar to a lambda in … Read more
I don’t know if it’s possible to change the default behavior of the shell, but you can at least format your output correctly, using io:format. Here is an example: 1> io:format(“~p~n”, [[65, 66, 67]]). “ABC” ok 2> io:format(“~w~n”, [[65, 66, 67]]). [65,66,67] ok And since the shell is only for experimenting / maintenance, io:format() should … Read more