topic Re: Problem with pstat_getproc in Operating System - Linux

Problem with pstat_getproc

Andreas Tsamis — Wed, 29 Jun 2005 01:20:36 GMT

Im using the following code (found in man pages) to get processes info, and i get an error saying

pstat_getproc failed: Value too large to be stored in data type

Source Code:
#define BURST ((size_t)10)

struct pst_status pst[BURST];
int i, count;
int idx = 0; /* index within the context */

while ((count=pstat_getproc(pst, sizeof(pst[0]),BURST,idx))>0) {
for (i = 0; i < count; i++) {
(void)printf("pid is %d, command is %s\n",pst[i].pst_pid, pst[i].pst_ucomm);
}
idx = pst[count-1].pst_idx + 1;
}

if (count == -1)
perror("pstat_getproc()");
#undef BURST

Re: Problem with pstat_getproc

Ermin Borovac — Wed, 29 Jun 2005 02:17:21 GMT

Try compiling your program with -D_PSTAT64. The following text is from pstat(2).

Notes
A wide (64 bit) version of the pstat interfaces are available for
narrow (32 bit) applications to use. A narrow application could use
the flag -D_PSTAT64 at compile time to switch to the wide interfaces.
Using this compiler flag in a narrow application is equivalent to
using the default interfaces on a wide system.

Re: Problem with pstat_getproc

Laurent Menase — Wed, 29 Jun 2005 02:20:16 GMT

#include
#include

#define BURST ((size_t)10)

main(){
struct pst_status pst[BURST];
int i, count;
int idx = 0; /* index within the context */

while ((count=pstat_getproc(pst, sizeof(pst[0]),BURST,idx))>0) {
for (i = 0; i < count; i++) {
(void)printf("pid is %d, command is %s\n",pst[i].pst_pid, pst[i].pst_ucomm);
}
idx = pst[count-1].pst_idx + 1;
}

if (count == -1)
perror("pstat_getproc()");
}
#undef BURST

I see no problem on my system. What is your system? do you have the error on compile or on exec?
How many process do you have?

Re: Problem with pstat_getproc

Andreas Tsamis — Wed, 29 Jun 2005 02:49:23 GMT

Flag -D_PSTAT64 doesn't work;
I'm working on an Itanium HPUX 11 v 2

I get the error when i execute the program.

This is the complete o/p:
I added some lines to o/p the pst size and no of processes.

bash-3.00# ./sysinf
Size of pst 776
pstat_getproc failed: Value too large to be stored in data type

*** 24 processes, 0 threads running

Re: Problem with pstat_getproc

Andreas Tsamis — Wed, 29 Jun 2005 03:20:08 GMT

Basically i'm trying to make a "light" version of "top" so i can send selectively data about resources and processes using tcpip to win and other unix machines.

Re: Problem with pstat_getproc

Ermin Borovac — Wed, 29 Jun 2005 04:28:28 GMT

I've just tried program that Laurent posted on 11iv2 itanium box and it worked fine when compiled with -D_PSTAT64 flag. If I don't use this flag error "Value too large" occurs.

$ cc -V
cc: HP aC++/ANSI C B3910B A.06.02 [Mar 24 2005]
$ cc -D_PSTAT64 pstat.c
$ ./a.out
pid is 0, command is swapper
pid is 1, command is init
pid is 8, command is ioconfigd
pid is 9, command is nfsktcpd
pid is 10, command is autofskd
pid is 11, command is lvmkd
pid is 12, command is lvmkd
pid is 13, command is lvmkd
pid is 14, command is lvmkd
pid is 15, command is lvmkd
pid is 16, command is lvmkd
...

If this still doesn't work for you try compiling 64-bit binary with +DD64 option to cc.

Re: Problem with pstat_getproc

Andreas Tsamis — Wed, 29 Jun 2005 04:47:54 GMT

Thanks is now working

Re: Problem with pstat_getproc

vinod_25 — Wed, 29 Jun 2005 04:48:00 GMT

hi andreas,

This error "pstat_getproc failed: Value too large to be stored in data type" oocours when a 32 bit application running on a 64 bit booted machine...

Check If the machine is booted in 64-bit mode, getconf KERNEL_BITS
and it should return "64".

32-bit applications that will be deployed on 64-bit HP-UX must use the
pstat() wrappers turned on with -D_PSTAT64 in order to function correctly
and remain compatible on 64-bit HP-UX

Good Luck

Vinod K

Re: Problem with pstat_getproc

Leo Lai — Thu, 19 Jan 2006 15:12:02 GMT

I just want to let you know that I had the exact same problem. I was trying to run the tool which you can find at http://h21007.www2.hp.com/dspp/tech/tech_TechSingleTipDetailPage_IDX/1,2366,5944,00.html

After reading this thread, I tried the two solutions. The -D_PSTAT64 flag didn't work for me; all the process info for all the processes would report the same number. Like the pid would be the same for all the processes.

But the +DD64 flag made it work perfectly. Thanks for your help.