java - Why doesn't dtruss show me the select system call in this JNI code? -

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while investigating jdk bug on mac os, ran system call trace output don't understand:

tomcat startup fails due 'java.net.socketexception invalid argument' on mac os x

the short version: on mac os, jdk uses select() instead of poll(). so, if more 1024 file descriptors allocated, deduced select() call in net_timeout fails resulting in socketexception 'invalid argument' message. however, when traced system calls, saw no evidence of select() system call, or call fails , sets einval, discounted potential cause.

i don't see call reduced test case i've created understand problem:

import java.io.*; import java.net.*;  public class selecttest {   public static void main(string[] args) throws exception {     for(int = 0; < 1024; i++) {       new fileinputstream("/dev/null");     }     serversocket socket = new serversocket(8080);     socket.accept();   } }

results in exception on mac os w/ jdk 1.7u5 , later:

exception in thread "main" java.net.socketexception: invalid argument     @ java.net.plainsocketimpl.socketaccept(native method)     @ java.net.abstractplainsocketimpl.accept(abstractplainsocketimpl.java:398)     @ java.net.serversocket.implaccept(serversocket.java:522)     @ java.net.serversocket.accept(serversocket.java:490)     @ selecttest.main(selecttest.java:12)

why don't see evidence of select() (or other failing) call when run test using sudo dtruss -a java selecttest?

        pid/thrd  relative  elapsd    cpu syscall(args)                  = return 45563/0x63a513:     85544       6      4 bind(0x412, 0x10dfc7738, 0x1c)          = 0 0 45563/0x63a513:     85605       6      3 listen(0x412, 0x32, 0x32)               = 0 0 45563/0x63a513:     85619       2      0 lseek(0x4, 0x37377ad, 0x0)              = 57898925 0 45563/0x63a513:     85622       4      2 read(0x4, "pk\003\004\n\0", 0x1e)               = 30 0 45563/0x63a513:     85622       1      0 lseek(0x4, 0x37377e0, 0x0)              = 57898976 0 45563/0x63a513:     85627       5      4 read(0x4, "\312\376\272\276\0", 0x3447)                 = 13383 0 45563/0x63a513:     86150      37     33 write(0x2, "exception in thread \"main\" ble\001\0", 0x1b)              = 27 0

i expect serversocket.accept call saw.

the berkeley sockets calls corresponding java's accept listen() , accept()

unfortunately i'm unable reproduce exception on linux. if use fd's before new serversocket(8080) get:

exception in thread "main" java.lang.unsatisfiedlinkerror: /usr/lib/jvm/java-7-oracle/jre/lib/amd64/libnet.so: /usr/lib/jvm/java-7-oracle/jre/lib/amd64/libnet.so: cannot open shared object file: many open files     @ java.lang.classloader$nativelibrary.load(native method)     @ java.lang.classloader.loadlibrary1(classloader.java:1939)     @ java.lang.classloader.loadlibrary0(classloader.java:1864)     @ java.lang.classloader.loadlibrary(classloader.java:1846)     @ java.lang.runtime.loadlibrary0(runtime.java:845)     @ java.lang.system.loadlibrary(system.java:1084)     @ sun.security.action.loadlibraryaction.run(loadlibraryaction.java:67)     @ sun.security.action.loadlibraryaction.run(loadlibraryaction.java:47)     @ java.security.accesscontroller.doprivileged(native method)     @ java.net.abstractplainsocketimpl.<clinit>(abstractplainsocketimpl.java:80)     @ java.net.serversocket.setimpl(serversocket.java:289)     @ java.net.serversocket.<init>(serversocket.java:230)     @ java.net.serversocket.<init>(serversocket.java:128)     @ selecttest.main(selecttest.java:15)

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