Which function returns LWP in Linux.
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From: Srinivas Nayak on 17 May 2010 02:30 Hi, For a process, we have different PIDs. For threads under a single processes, we have different LWP id, but same PID in Linux. ex. root(a)pc:/home/srinivas# ps -eLf UID PID PPID LWP C STIME TIME CMD root 100 1 100 0 May13 00:00:02 ./a.out root 100 1 102 0 May13 00:00:00 ./a.out getpid() function returns PID of a process. Which function retuns LWP id for thread? Sincerely, Srinivas Nayak -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Jaswinder Singh Rajput on 17 May 2010 03:00 Hello, On Mon, May 17, 2010 at 11:57 AM, Srinivas Nayak <sinu.nayak2001(a)gmail.com> wrote: > Hi, > > For a process, we have different PIDs. For threads under a single > processes, we have different LWP id, but same PID in Linux. > ex. > > root(a)pc:/home/srinivas# ps -eLf > UID � � � �PID �PPID � � LWP �C STIME � � � TIME � � CMD > root � � � 100 � � 1 � � 100 �0 May13 � � � 00:00:02 ./a.out > root � � � 100 � � 1 � � 102 �0 May13 � � � 00:00:00 ./a.out > > getpid() function returns PID of a process. > Which function retuns LWP id for thread? > You are asking procps question in LKML. Please check http://procps.sourceforge.net/ Download propps package, read source code and you will get the reply. Thanks, -- Jaswinder Singh. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: KOSAKI Motohiro on 17 May 2010 03:10 > Hi, > > For a process, we have different PIDs. For threads under a single > processes, we have different LWP id, but same PID in Linux. > ex. > > root(a)pc:/home/srinivas# ps -eLf > UID PID PPID LWP C STIME TIME CMD > root 100 1 100 0 May13 00:00:02 ./a.out > root 100 1 102 0 May13 00:00:00 ./a.out > > getpid() function returns PID of a process. > Which function retuns LWP id for thread? gettid() -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Jaswinder Singh Rajput on 17 May 2010 03:40 Hello KOSAKI-san, On Mon, May 17, 2010 at 12:33 PM, KOSAKI Motohiro <kosaki.motohiro(a)jp.fujitsu.com> wrote: >> Hi, >> >> For a process, we have different PIDs. For threads under a single >> processes, we have different LWP id, but same PID in Linux. >> ex. >> >> root(a)pc:/home/srinivas# ps -eLf >> UID � � � �PID �PPID � � LWP �C STIME � � � TIME � � CMD >> root � � � 100 � � 1 � � 100 �0 May13 � � � 00:00:02 ./a.out >> root � � � 100 � � 1 � � 102 �0 May13 � � � 00:00:00 ./a.out >> >> getpid() function returns PID of a process. >> Which function retuns LWP id for thread? > > gettid() > gettid() is linux specific and not supported in glibc. Normally application do not use gettid(), even procps is not using it, that why I suggested Srinivas to check procps source to find the best solution for it. Thanks, -- Jaswinder Singh. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Srinivas Nayak on 17 May 2010 06:20
> > You are asking procps question in LKML. > Dear Jaswinder, I am new to linux mailing lists. Thought, this process id related question can only be answered by linux kernel developers, as they may be working with this almost everyday. And more to this, I searched in the Internet for LWP id, but found no positive answer. Many places gettid was the answer, but it doesn't work. I apologize, if lkml is not the best place to ask programming related questions. It would be kind, if you let me know the correct mailing list where general linux programming discussions happen. To my find, linux-c-programming mailing list is not so active. After some more research, i foind that syscall(SYS_gettid) returns LWP id. Isn't this correct? Sincerely, Srinivas Nayak -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |