is open() truly thread-safe?

I'm getting the following race condition detected by DRDT, on SPARC/Solaris 10 6/06:

38 static char random_device_name[] = "/dev/urandom";

68if ((random_fildes = open (random_device_name, O_RDONLY)) < 0)

69 {

70 log_message (APP_FATAL, FILE_LINE "cannot open %s; errno=%d (%s); exiting!",

71 random_device_name, errno, errno_string (errno));

72 exit (EXIT_FAILURE);

73 }

Access 1: Write

isptsfd + 0x00000050

Access 2: Write

isptsfd + 0x00000050

_open + 0x00000050

open + 0x00000064

MessageTransfer::MessageTransfer(const char*,const char*,const char*,const char*,const char*) + 0x0000051C, line 68 in alternate source context "messaging.cc"

MessageServer::MessageServer(const char*,const char*,const char*,const char*,const char*) + 0x00000074, line 393 in alternate source context "messaging.cc"

fragment_request_reader_thread_main + 0x000001CC, line 1384 in "fraggen.cc"

_lwp_start + 0x00000000

Two separate threads are trying to open a file descriptor for the same file. Is that what's causing this conflict, or is it something more general within open()? (random_fildes is local to each thread, so that's not the conflict.)

[1248 byte] By [herteg] at [2007-11-26 10:11:59]