Software Development

vprintf segfault on Ubuntu Linux 15.10

I have a C program with a ‘print’ function that accepts a format string and variable list of arguments, similar to printf style functions. The function simply prints to stdout and also to a logfile. void print(const char* format, …) { pthread_mutex_lock(&logfile_mutex);   va_list args; va_start(args,format);   vprintf(format,args); fflush(stdout);   fprintf(logfile,"%d ",milli_timer()); vfprintf(logfile,format,args); fflush(logfile);   […]

local array causes segfault

Recently while working on a C program I was intermittently getting a segfault. The code appeared correct yet it would inexplicably crash, seemingly at random. I compiled the program with the ‘-g’ flag to enable debugging symbols, and discovered I was dealing with the dreaded stack overflow. Exception: STATUS_STACK_OVERFLOW at rip=00100414BC6 The line of code […]

Swafford Consulting Hired for TrACER-R Project

I’m very pleased and excited to announce that Swafford Consulting has been selected by IVIR Inc. (Information Visualization and Innovative Research) to rewrite and expand the Training/Test Assessment Capabilities and Reporting for Research (TrACER-R) System. The following information has been publicly released by IVIR and posted on this website with permission from them. TrACER is […]

JBoss 7 – Channel end notification received, closing channel Channel ID (inbound) of Remoting connection to null

As mentioned in a previous post I’ve recently upgraded to JBoss EAP 6.2 / AS 7.1. For a few weeks after the transition a small set of users were complaining about a ‘channel closed’ error. Few errors have driven me crazier than this one. It was not a good time, for me or the users. […]

JBoss 7.x remoting + security-domain

I just recently updated an application to Red Hat’s EAP 6.2.0 platform, which uses the JBoss 7.3 Application Server under the hood. I’ve been a JBoss user for a long time now. In fact, this application started life on JBoss 3.something, and I (sometimes with the help of other devs) have seen it upgraded to […]

JBoss + HornetMQ + Encrypted FS + AIO

I wrestled with an …. interesting issue today that sunk most of my morning. I was working on an EJB3 application with a local installation of JBoss 6.1. In fact, I worked on the same application last Friday. Today, however, when I started the server I was greeted with this: 16:23:28,800 ERROR [org.hornetq.ra.inflow.HornetQActivation] Unable to […]

Functional Programming Principles in Scala

I recently finished a Coursera class entitled ‘Functional Programming Principles in Scala’, taught by none other than Martin Odersky himself. For those that don’t know, Martin is the creator of the Scala language and a professor at École Polytechnique Fédérale de Lausanne. Read it and weep: scala_certificate For those contemplating taking this class, I encourage […]

JBoss 6.1.0.Final + HornetQ Timing Issue

I had one of those ‘one line fix’ problems on Monday that took most of my day to figure out. It was one of those problems that makes perfect sense in retrospect, but when I was in the trench the solution was anything but obvious. A big chunk of my time these days goes towards […]

Groovy’s MetaClass

I’m not a big fan of dynamic languages, but I recently came across a situation where Groovy’s MetaClass came in extremely handy. The situation was this: I am maintaining a Grails application that interfaces with a Java based codebase. One of the methods in this Java codebase returns a list of Data Transfer Objects (DTOs). […]

A First Look at Scala

Scala has been on my “personal radar” for two or three years now, but it hadn’t quite bubbled to the top of the list until recently. I’ve been playing around with it off and on for a couple of months now; not enough to get too deep into it, but I’ve gotten a taste. My […]