/dev/dump

I've been noticing more and more lately that we have a plethora of libraries and programs written for Go, which don't work on one platform or another.  The root cause of these is often the use of direct system call coding to system calls such as ioctl().  On some platforms (illumos/solaris!) there is no such system call. The Problems But this underscores a far far worse problem, that has become common (mal)-practice in the Go community.  That is, the coding of system calls directly into high level libraries and even application programs.  For example, it isn't uncommon to see something like this (taken from termbox-go ): func tcsetattr(fd uintptr, termios *syscall_Termios) error {         r, _, e := syscall.Syscall(syscall.SYS_IOCTL,                 fd, uintptr(syscall_TCSETS), uintptr(unsafe.Pointer(termios)))         if r != 0 {             ...

I'm happy to announce that I feel I've wrapped up Govisor to a point where its ready for public consumption. Govisor is a service similar to supervisord , in that it can be used to manage a bunch of processes.  However, it is much richer in that it understands process dependencies, conflicts, and also offers capabilities for self-healing, and consolidated log management. It runs as an ordinary user process, and while it has some things in common with programs like init, upstart, and Solaris SMF, it is not a replacement for any of those things.  Instead think of this is a portable way to manage a group of processes without requiring root.  In my case I wanted something that could manage a tree of microservices that was deployable by normal users.  Govisor is my answer to that problem. Govisor is also written entirely in Go, and is embeddable in other projects.  The REST server interface uses a stock http.ServeHTTP interface, so it can be used with various ...

As a PSA (public service announcement), I'm reporting here that updating your Yosemite system to 10.10.3 is incredibly toxic if you use WiFi. I've seen other reports of this, and I've experienced it myself.  What happened is that the update for 10.10.3 seems to have done something tragically bad to the WiFi drivers, such that it completely hammers the network to the point of making it unusable for everyone else on the network. I have late 2013 iMac 27", and after I updated, I found that other systems started badly badly misbehaving.  I blamed my ISP, and the router, because I was seeing ping times of tens of seconds ! (No, not milliseconds, seconds!!!   In one case I saw responses over 64 seconds.)  This was on other systems that were not upgraded.  Needless to say, that basically left the network unusable. (The behavior was cyclical -- I'd get a few tens of seconds where pings to 8.8.8.8 would be in the 20 msec range, and then it would start to jump up v...

I recently decided to have a look back at some old  stuff I wrote.  Blast from the past stuff.  One of the things I decided to look at was the very first open source program I wrote -- something called vtprint . vtprint is a tool that borrowed ideas stolen from the pine mail program.  This comes from the days of serial dialups, and legacy ( Kermit  or ProComm for those who remember such things) serial connectivity over 14.4K modems.  Printing a file on a remote server was hard back then; you could transfer the file using xmodem using rx(1), or its "newer" variants, rb(1) or rz(1), but this was awkward.  It turns out that most physical terminals had support for an escape sequence that would start hardcopy to a locally attached printer, and another that would stop it.  And indeed, many terminal emulators have the same support.  (I added support for this myself to the rxvt (1) terminal emulator back in the mid 90's, so any emulators derived...

As part of a work-related project, I'm writing code that needs to resolve DNS names using Go , on illumos . While doing this work, I noticed a very surprising thing.  When a host has both IPv6 and IPv4 addresses associated with a name (such as localhost ), Go prefers to resolve to the IPv4 version of the name, unless one has asked specifically for v6 names. This flies in the fact of existing practice on illumos & Solaris systems, where resolving a name tends to give an IPv6 result, assuming that any IPv6 address is plumbed on the system.  (And on modern installations, that is the default -- at least the loopback interface of ::1 is always plumbed by default.  And not only that, but services listening on that address will automatically serve up both v6 and v4 clients that connect on either ::1 or 127.0.0.1.) The rationale for this logic is buried in the Go net/ipsock.go file, in comments for the function firstFavoriteAddr  () : 76 // We'll take any...

What is mangos? Those of you who follow me may have heard about this project I've created called mangos . Mangos is a lightweight messaging system designed to be wire compatible with nanomsg , but is implemented entirely in Go . There is a very nice write up of mangos by Tyler Treat, which might help explain some things. Recent Activity As a consequence of a few things, the last two weeks has seen a substantial rise of use of mangos. First off, there was Tyler's excellent article.  (By the way, he's done a series comparing and contrasting other messaging systems -- highly recommended reading.) Second, mangos got mentioned on Hacker News .  That drew a large number visitors to my github repo. Then another open source project, Goq , switched from using libnanomsg to mangos, using the compatibility shim I provided for such use.  As a consequence of that work, several bugs were identified, and subsequently squashed. The upshot of all that is that I saw t...

If you follow illumos very closely, you may already know some of this. A New Fork Several months ago, I forked illumos-gate (the primary source code repository for the kernel and system components of illumos) into illumos-core . I had started upstreaming my work from illumos-core into illumos-gate.  I've since ceased that effort, largely because I simply have no time for the various arguments that my work often generates.  I think this is largely because my vision for illumos is somewhat different from that of other folks, and sadly illumos proper lacks anything resembling a guiding vision now, which means that only entirely non-contentious changes can get integrated into illumos. However, I still want to proceed apace with illumos-core, because I believe that work has real value, and I firmly believe that my vision for illumos is the one that will lead to greater adoption by users, and by distributors as well, since much of what I'm trying to achieve in illumos-g...