C++Talk.NET C++ language newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  Return code of 4294967295 (UINT_MAX)          C++Talk.NET Forum Index -> C++ language (comp.lang.c++) View previous topic :: View next topic   Author Message Vineet Guest Posted: Tue Jun 29, 2004 7:18 pm    Post subject: Return code of 4294967295 (UINT_MAX) If anybody has any insight into this problem I'm running into I would really appreciate if you could write to me... I'm running a simple C++ program on Solaris 8 that forks and execs a bunch of processes. It's been running fine for years, but now that I've moved to faster hardware, I'm running into a problem that surfaces more frequently as the hardware I'm using gets better/faster -- it seems like some sort of race condition issue. Basically, at random, a handful of the process immediately fail (before actually doing anything) and return an exit code of 4294967295 (UINT_MAX). I imagine that this is just an umbrella status code for all unexpected/unexplained errors, so I'm not sure if it means anything? One thing to note is that if I just trap this error and execute the process again, it runs fine. It just seems like at the time the fork/exec takes place, something in the system temporarily screws up but I don't know what. Of course I do have a workaround (just re-run the process) but I'd like to know what's going on. If anybody has encounted anything like this, please let me know, and I can provide you with more information if need be...thanks. Back to top Dan Mercer Guest Posted: Tue Jun 29, 2004 8:31 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) "Vineet" <vineet.aggarwal (AT) mantas (DOT) com> wrote : If anybody has any insight into this problem I'm running into I would : really appreciate if you could write to me... : : I'm running a simple C++ program on Solaris 8 that forks and execs a : bunch of processes. It's been running fine for years, but now that : I've moved to faster hardware, I'm running into a problem that : surfaces more frequently as the hardware I'm using gets better/faster : -- it seems like some sort of race condition issue. Sounds like fork is failing. If the program is not running as root, you are probably exceeding maxuproc (see your kernel parameters documentation). If it is running as root, you're exceeding nprocs. Nprocs determines how many structures controlling processes are created. Maxuproc determines how many processes a user can have - it should always be less than half nprocs and is usually quite a bit smaller. Default parameters for most machines are not set up properly to handle heavy usage by a small number of programs or users. One other problem, it is likely that you are not handling wait situations properly and may have a large number of zombie processes. These will consume limited process resources. Even if your processes are being reaped by init it's possible to get in race conditions where zombie's are created faster than init can reap them. Without seeing any actual code - like your fork-exec code - it's impossible to say. Post some code if you want more help. Good luck, Dan : : Basically, at random, a handful of the process immediately fail : (before actually doing anything) and return an exit code of 4294967295 : (UINT_MAX). I imagine that this is just an umbrella status code for : all unexpected/unexplained errors, so I'm not sure if it means : anything? It's a -1. : : One thing to note is that if I just trap this error and execute the : process again, it runs fine. It just seems like at the time the : fork/exec takes place, something in the system temporarily screws up : but I don't know what. Of course I do have a workaround (just re-run : the process) but I'd like to know what's going on. : : If anybody has encounted anything like this, please let me know, and I : can provide you with more information if need be...thanks. Back to top joe@invalid.address Guest Posted: Tue Jun 29, 2004 8:48 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) [email]vineet.aggarwal (AT) mantas (DOT) com[/email] (Vineet) writes: Quote: If anybody has any insight into this problem I'm running into I would really appreciate if you could write to me... I'm running a simple C++ program on Solaris 8 that forks and execs a bunch of processes. It's been running fine for years, but now that I've moved to faster hardware, I'm running into a problem that surfaces more frequently as the hardware I'm using gets better/faster -- it seems like some sort of race condition issue. Basically, at random, a handful of the process immediately fail (before actually doing anything) and return an exit code of 4294967295 (UINT_MAX). I imagine that this is just an umbrella status code for all unexpected/unexplained errors, so I'm not sure if it means anything? That's -1, which the man page documents fork() to return in case of an error. In that case you should check to see what the value of errno is. You can get a textual version of the error by calling either perror() or strerror(errno). That will probably enlighten things. Joe -- Folks who don't know why America is the Land of Promise should be here during an election campaign. -- Milton Berle Back to top Howard Guest Posted: Tue Jun 29, 2004 8:51 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) Quote: Post some code if you want more help. Really, guys, this discussion belongs off-line or in a forum that is more appropriate. This newsgroup doesn't discuss platform-specific stuff like processes/threads, etc. This is a language newsgroup. -Howard Back to top Keith Thompson Guest Posted: Wed Jun 30, 2004 3:11 am    Post subject: Re: Return code of 4294967295 (UINT_MAX) "Howard" <alicebt (AT) hotmail (DOT) com> writes: Quote: Post some code if you want more help. Really, guys, this discussion belongs off-line or in a forum that is more appropriate. This newsgroup doesn't discuss platform-specific stuff like processes/threads, etc. This is a language newsgroup. This thread is cross-posted to comp.lang.c++, comp.unix.programmer, comp.lang.c, and comp.unix.solaris. It's probably appropriate in comp.unix.programmer and/or comp.unix.solaris, which do discuss platform-specific stuff. Please trim the newsgroups line on any followups. -- Keith Thompson (The_Other_Keith) [email]kst-u (AT) mib (DOT) org[/email] <http://www.ghoti.net/~kst> San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst> We must do something. This is something. Therefore, we must do this. Back to top Casper H.S. Dik Guest Posted: Wed Jun 30, 2004 7:38 am    Post subject: Re: Return code of 4294967295 (UINT_MAX) [email]vineet.aggarwal (AT) mantas (DOT) com[/email] (Vineet) writes: Quote: Basically, at random, a handful of the process immediately fail (before actually doing anything) and return an exit code of 4294967295 (UINT_MAX). I imagine that this is just an umbrella status code for all unexpected/unexplained errors, so I'm not sure if it means anything? A process cannot fail with an exit code of 4294967295 (UINT_MAX); the only valid exit codes are between 0 and 255 (inclusive). So the first question is: what is returning -1 (whatever returns a number with all bits set is more ikely to return -1 than UINT_MAX) Quote: One thing to note is that if I just trap this error and execute the process again, it runs fine. It just seems like at the time the fork/exec takes place, something in the system temporarily screws up but I don't know what. Of course I do have a workaround (just re-run the process) but I'd like to know what's going on. Have you tried "truss -f"? Casper -- Expressed in this posting are my opinions. They are in no way related to opinions held by my employer, Sun Microsystems. Statements on Sun products included here are not gospel and may be fiction rather than truth. Back to top Prateek R Karandikar Guest Posted: Wed Jun 30, 2004 2:12 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) Quote: If anybody has any insight into this problem I'm running into I would really appreciate if you could write to me... I'm running a simple C++ program on Solaris 8 that forks and execs a bunch of processes. It's been running fine for years, but now that I've moved to faster hardware, I'm running into a problem that surfaces more frequently as the hardware I'm using gets better/faster -- it seems like some sort of race condition issue. Basically, at random, a handful of the process immediately fail (before actually doing anything) and return an exit code of 4294967295 (UINT_MAX). I imagine that this is just an umbrella status code for all unexpected/unexplained errors, so I'm not sure if it means anything? One thing to note is that if I just trap this error and execute the process again, it runs fine. It just seems like at the time the fork/exec takes place, something in the system temporarily screws up but I don't know what. Of course I do have a workaround (just re-run the process) but I'd like to know what's going on. If anybody has encounted anything like this, please let me know, and I can provide you with more information if need be...thanks. And your question about Standard C++ is? -- -- Abstraction is selective ignorance. -Andrew Koenig -- -- Back to top Vineet Guest Posted: Wed Jun 30, 2004 8:51 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) Thank you very much for your replies. I apologize if the post was not appropriate for this newsgroup -- it's my first time posting to one of these, and now that I know what the appropriate groups are, I will only post any followups to this thread on those newsgroups (comp.unix.programmer and comp.unix.solaris). For those of you that offered suggestions, please see those groups if you wish to follow this thread through. As for the post from Prateek, I now understand that this wasn't the right newsgroup, but I don't think it's necessary to be a jerk about it. There were 2 previous posts that already pointed out my mistake, so for you to post an extraneous message just to flame me is just as bad if not worse than posting a message to the wrong newsgroup. Back to top Vineet Guest Posted: Wed Jun 30, 2004 8:51 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) Thank you very much for your replies. I apologize if the post was not appropriate for this newsgroup -- it's my first time posting to one of these, and now that I know what the appropriate groups are, I will only post any followups to this thread on those newsgroups (comp.unix.programmer and comp.unix.solaris). For those of you that offered suggestions, please see those groups if you wish to follow this thread through. As for the post from Prateek, I now understand that this wasn't the right newsgroup, but I don't think it's necessary to be a jerk about it. There were 2 previous posts that already pointed out my mistake, so for you to post an extraneous message just to flame me is just as bad if not worse than posting a message to the wrong newsgroup. Back to top LibraryUser Guest Posted: Wed Jun 30, 2004 9:34 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) Howard wrote: Quote: .... snip ... Really, guys, this discussion belongs off-line or in a forum that is more appropriate. This newsgroup doesn't discuss platform-specific stuff like processes/threads, etc. This is a language newsgroup. So, instead of simply muttering, set followups. -- Replies should be to the newsgroup Replace this line to publish your e-mail address. Back to top all mail refused Guest Posted: Fri Jul 02, 2004 5:03 pm    Post subject: Re: Return code of 4294967295 (UINT_MAX) In article <40e26dfe$0$48933$e4fe514c (AT) news (DOT) xs4all.nl>, Casper H.S. Dik wrote: Quote: fork/exec takes place, something in the system temporarily screws up but I don't know what. Of course I do have a workaround (just re-run the process) but I'd like to know what's going on. Have you tried "truss -f"? This might help spot the difference between 2 truss outputs (which you name on the command line). Random interleaving of parent and child contributions is left for you to sort out in this version. I might have done more if I'd thoght I'd need it regularly. #!/usr/bin/perl -w sub display { for ($ln=$lineno-5; $ln<=$lineno; $ln++) { next if ($ln<1); printf("%s(%d) %sn", $ARGV[0], $ln, $left{$ln}); } print "n"; for ($ln=$lineno-5; $ln<=$lineno; $ln++) { next if ($ln<1); printf("%s(%d) %sn", $ARGV[1], $ln, $right{$ln}); } } sub lineparse { $_=shift; TEST: while (1) { $syscall="NA"; $result="NA"; if ($_ =~ /s(S+)$/) { $result=$1; } if ($_ =~ /^d+:s+([^(]+)(/) { $syscall=$1; last TEST; } if ($_ =~ /^d+:s+***.****$/) { print "$_n"; last TEST; } die("RE not matched: $_n"); } } ####################################### open(LFH, "<$ARGV[0]") or die("open $ARGV[0]"); open(RFH, "<$ARGV[1]") or die("open $ARGV[1]"); for($lineno=1;;$lineno++) { $left= $right=<RFH>; if ( (!defined($left)) && (defined($right)) ) { die("end of $ARGV[0]"); } if ( (defined($left)) && (!defined($right)) ) { die("end of $ARGV[1]"); } chomp($left); chomp($right); #print "DEBUG $leftn"; lineparse($left); $left_syscall=$syscall; $left_result=$result; $left{$lineno}=$left; lineparse($right); $right_syscall=$syscall; $right_result=$result; $right{$lineno}=$right; if ($right_syscall ne $left_syscall) { print "syscall differencenn"; display(); exit(1); } if ( ($right_result =~ /^d+$/) && ($left_result !~ /^d+$/)) { print "Non-Numerical Result (left)nn"; display(); exit(1); } if ( ($right_result !~ /^d+$/) && ($left_result =~ /^d+$/)) { print "Non-Numerical Result (right)nn"; display(); exit(1); } if ( ( ("0" eq $right_result) && ("0" ne $left_result) ) || ( ("0" ne $right_result) && ("0" eq $left_result) ) ){ print "Numerical Resultsnn"; display(); exit(1); } } exit(0); -- Elvis Notargiacomo master AT barefaced DOT cheek http://www.notatla.org.uk/goen/ Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         C++Talk.NET Forum Index -> C++ language (comp.lang.c++) All times are GMT Page 1 of 1   Jump to: Select a forum C/C++----------------C LanguageC Language (Moderated)C++ Language (Moderated)C++ language (comp.lang.c++)C++ language, library and standards Non-English C/C++ Newsgroups----------------C++ (German)C++ (French)  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.