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    <p>There's a few mechanisms I can suggest to try to track down this problem.</p> <p>First, use <code>strace(1)</code> and <code>ltrace(1)</code> on <code>nodejs</code>:</p> <pre><code>strace -o /tmp/node.strace -fF nodejs script.js ltrace -o /tmp/node.ltrace -f nodejs script.js </code></pre> <p>Then look through the <code>/tmp/node.*</code> files to discover what it was doing moments before it crashed. <strong>Edit</strong>: <code>strace(1)</code> reports the <em>system calls</em> that the program makes; as programs interact with the outside world via system calls, it's often the fastest mechanism to finding bugs. <code>ltrace(1)</code> reports dynamic library calls, which is frequently a lot more information about the internal workings of the program. Both are useful.</p> <p>Second, run <code>dmesg &gt; /tmp/dmesg</code> and look through the <code>dmesg</code> output for the segfault information, it'll look like this:</p> <pre><code>[332430.652393] npviewer.bin[13508]: segfault at 418 ip 00000000f6086d16 sp 00000000ffd8b018 error 6 in libflashplayer.so[f5e19000+b5f000] </code></pre> <p>That's an Adobe Flash crash; comparing the addresses against <code>readelf -s</code> output on the program, you might be able to guess how <em>far</em> into the function the segfault is occurring, which might help when reading the source code. (It's a long shot to guess by address how far you are into a function, but I've found it useful to know if I should look near the start or end of a function.)</p> <p>Third, you could run the program with <code>valgrind(1)</code>:</p> <pre><code>valgrind nodejs script.js </code></pre> <p>Valgrind is an impressive tool that might require a fair amount of learning to really <em>know</em>. The little I've used it, I've been impressed, but I can't give as decent a guide as the other simpler tools.</p> <p>Fourth, you could run <code>nodejs</code> under <code>gdb</code>:</p> <pre><code>gdb --args nodejs script.js </code></pre> <p>When it dies, run <code>bt</code> to get a backtrace. <code>gdb</code> is also an impressive program, and you could probably find the exact line that fails using it, but it too takes a fair amount of learning to really <em>know</em>. I've been lucky enough that backtraces were usually enough to find the fault.</p> <p>With luck you'll be pointed to the exact function that failed, and <code>ltrace(1)</code> will give you the arguments of that function. This'll hopefully be enough to track down the specific bug.</p>
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    1. POnodejs-0.4.2 segfault on start (Fixed in v 0.4.5)
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    1. CO+1 for all the good suggestions.now gdb shows `No Stack`. All I get in the dmesg output is `[ 3736.369391] npviewer.bin[5879]: segfault at 0 ip (null) sp bf81d3dc error 14 in npviewer.bin[8048000+2a000]`
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    2. COstrace shows `6346 <... nanosleep resumed> NULL) = 0 6346 nanosleep({0, 900000}, <unfinished ...> 6345 write(2, "node.js:0\n", 10) = 10 6345 --- SIGSEGV (Segmentation fault) @ 0 (0) --- 6346 +++ killed by SIGSEGV +++` ...Wow I was thinking along the lines of missing dependencies. I'll have a stab at the source anyway. :)
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    3. CO@Adil Mehmood, heh, that's an Adobe Flash crash in your `dmesg`. Stupid buggy pile... :) I'm surprised about `gdb`'s `No Stack`, I've never seen that one before. How about the `ltrace` output?
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