NetNews Usenet Archive 1992 #16/NN_1992_16.iso/spool/comp/unix/question/9268

Text File | 1992-07-21 | 11.2 KB | 521 lines

Newsgroups: comp.unix.questions
Path: sparky!uunet!usc!sol.ctr.columbia.edu!cs.columbia.edu!amir
From: [e-mail] (Amiran Eliashvili)
Subject: Memory leaks
Message-ID: <[e-mail]>
Sender: [e-mail] (The Daily News)
Organization: Columbia University Department of Computer Science
References: <[e-mail]>
Date: Wed, 22 Jul 1992 03:09:06 GMT
Lines: 509



Hi all,



I am having problems running ptrace(2) succesfully. I am trying to get
the first 100 dynamic memory location of a running process.


What I am trying to do is to fork a process and get its pid and then
exec the executable I am trying to trace. Everything seems to work
except ptrace(). This is my first time using this system call so I am
not quite sure if I am using it correctly. Here is a sample program
that shows my attepmts at using ptrace(2). I'll appreciate greatly any
pointers of how to gp about using ptrace correctly.


                        Many Thanks In advance
                           --Amiran

---- Sample program -----



/*
 *
 * Design
 * _______
 *
 * The parent forks a child and gets its pid.
 * Then, we set the child to have it traced by the parent
 * at each time we inrement the data segment by four
 * and get all the registers (please reffer to
 * machine/reg.h to get the name of the registers
 * I am printing Thanks.
 *
 *
 */


#include <stdio.h>
#include <machine/reg.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/wait.h>

main(argc, argv)
     int argc;
     char *argv[];
{

  enum ptracereq request;

  struct  regs addr;
  int data;
  char *addr2;
  int i=1;
  int pid;

  int tmp;


  if (( pid = fork()) == 0){
    ptrace( PTRACE_TRACEME, 0, 0, 0);
    execl(argv[1],argv[1],0);
    exit(1);
  }
  for(i = 0; i < 100; i++){
    wait((int *)0);
    tmp += sizeof(int);
/*    if(ptrace(PTRACE_POKEDATA,pid,tmp,i) == -1)
      exit(-1);  */



/*    if(ptrace(PTRACE_ATTACH,pid,0,0) == -1)
      exit(-1);   */
    if(ptrace(PTRACE_GETREGS,pid,&addr,i) == -1)
      exit(-1);

    printf("addr.r_pc = %d\n",addr.r_pc);
    printf("addr.r_npc = %u\n",addr.r_npc);
    printf("addr.r_psr = %u\n",addr.r_psr);
    printf("addr.r_y = %u\n",addr.r_y);
    printf("addr.r_g1 = %u\n",addr.r_g1);
    printf("addr.r_g1 = %u\n\n",addr.r_g1);

  }
  /* traced process should resume execution */
  ptrace(PTRACE_CONT, pid, 1, 0);

}  /* end */


Newsgroups: comp.unix.questions, comp.unix.w
Subject: ptrace(2) problems
Summary:
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Organization: Columbia University Department of Computer Science
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Hi all,



I am having problems running ptrace(2) succesfully. I am trying to get
the first 100 dynamic memory location of a running process.


What I am trying to do is to fork a process and get its pid and then
exec the executable I am trying to trace. Everything seems to work
except ptrace(). This is my first time using this system call so I am
not quite sure if I am using it correctly. Here is a sample program
that shows my attepmts at using ptrace(2). I'll appreciate greatly any
pointers of how to gp about using ptrace correctly.


                        Many Thanks In advance
                           --Amiran

---- Sample program -----



/*
 *
 * Design
 * _______
 *
 * The parent forks a child and gets its pid.
 * Then, we set the child to have it traced by the parent
 * at each time we inrement the data segment by four
 * and get all the registers (please reffer to
 * machine/reg.h to get the name of the registers
 * I am printing Thanks.
 *
 *
 */


#include <stdio.h>
#include <machine/reg.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/wait.h>

main(argc, argv)
     int argc;
     char *argv[];
{

  enum ptracereq request;

  struct  regs addr;
  int data;
  char *addr2;
  int i=1;
  int pid;

  int tmp;


  if (( pid = fork()) == 0){
    ptrace( PTRACE_TRACEME, 0, 0, 0);
    execl(argv[1],argv[1],0);
    exit(1);
  }
  for(i = 0; i < 100; i++){
    wait((int *)0);
    tmp += sizeof(int);
/*    if(ptrace(PTRACE_POKEDATA,pid,tmp,i) == -1)
      exit(-1);  */



/*    if(ptrace(PTRACE_ATTACH,pid,0,0) == -1)
      exit(-1);   */
    if(ptrace(PTRACE_GETREGS,pid,&addr,i) == -1)
      exit(-1);

    printf("addr.r_pc = %d\n",addr.r_pc);
    printf("addr.r_npc = %u\n",addr.r_npc);
    printf("addr.r_psr = %u\n",addr.r_psr);
    printf("addr.r_y = %u\n",addr.r_y);
    printf("addr.r_g1 = %u\n",addr.r_g1);
    printf("addr.r_g1 = %u\n\n",addr.r_g1);

  }
  /* traced process should resume execution */
  ptrace(PTRACE_CONT, pid, 1, 0);

}  /* end */


Newsgroups: comp.unix.questions,comp.unix.admin,comp.unix.wizards,comp.unix.ultrix
Subject: ptrace(2) problems
Summary:
Expires:
Sender:
Followup-To:
Distribution:
Organization: Columbia University Department of Computer Science
Keywords:



Hi all,



I am having problems running ptrace(2) succesfully. I am trying to get
the first 100 dynamic memory location of a running process.


What I am trying to do is to fork a process and get its pid and then
exec the executable I am trying to trace. Everything seems to work
except ptrace(). This is my first time using this system call so I am
not quite sure if I am using it correctly. Here is a sample program
that shows my attepmts at using ptrace(2). I'll appreciate greatly any
pointers of how to gp about using ptrace correctly.


                        Many Thanks In advance
                           --Amiran

---- Sample program -----



/*
 *
 * Design
 * _______
 *
 * The parent forks a child and gets its pid.
 * Then, we set the child to have it traced by the parent
 * at each time we inrement the data segment by four
 * and get all the registers (please reffer to
 * machine/reg.h to get the name of the registers
 * I am printing Thanks.
 *
 *
 */


#include <stdio.h>
#include <machine/reg.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/wait.h>

main(argc, argv)
     int argc;
     char *argv[];
{

  enum ptracereq request;

  struct  regs addr;
  int data;
  char *addr2;
  int i=1;
  int pid;

  int tmp;


  if (( pid = fork()) == 0){
    ptrace( PTRACE_TRACEME, 0, 0, 0);
    execl(argv[1],argv[1],0);
    exit(1);
  }
  for(i = 0; i < 100; i++){
    wait((int *)0);
    tmp += sizeof(int);
/*    if(ptrace(PTRACE_POKEDATA,pid,tmp,i) == -1)
      exit(-1);  */



/*    if(ptrace(PTRACE_ATTACH,pid,0,0) == -1)
      exit(-1);   */
    if(ptrace(PTRACE_GETREGS,pid,&addr,i) == -1)
      exit(-1);

    printf("addr.r_pc = %d\n",addr.r_pc);
    printf("addr.r_npc = %u\n",addr.r_npc);
    printf("addr.r_psr = %u\n",addr.r_psr);
    printf("addr.r_y = %u\n",addr.r_y);
    printf("addr.r_g1 = %u\n",addr.r_g1);
    printf("addr.r_g1 = %u\n\n",addr.r_g1);

  }
  /* traced process should resume execution */
  ptrace(PTRACE_CONT, pid, 1, 0);

}  /* end */


Newsgroups: comp.unix.wizards
Subject: ptrace(2) problems
Summary:
Expires:
Sender:
Followup-To:
Distribution:
Organization: Columbia University Department of Computer Science
Keywords:



Hi all,



I am having problems running ptrace(2) succesfully. I am trying to get
the first 100 dynamic memory location of a running process.


What I am trying to do is to fork a process and get its pid and then
exec the executable I am trying to trace. Everything seems to work
except ptrace(). This is my first time using this system call so I am
not quite sure if I am using it correctly. Here is a sample program
that shows my attepmts at using ptrace(2). I'll appreciate greatly any
pointers of how to gp about using ptrace correctly.


                        Many Thanks In advance
                           --Amiran
Please respond via e-mail

---- Sample program -----



/*
 *
 * Design
 * _______
 *
 * The parent forks a child and gets its pid.
 * Then, we set the child to have it traced by the parent
 * at each time we inrement the data segment by four
 * and get all the registers (please reffer to
 * machine/reg.h to get the name of the registers
 * I am printing Thanks.
 *
 *
 */


#include <stdio.h>
#include <machine/reg.h>
#include <signal.h>
#include <sys/ptrace.h>
#include <sys/wait.h>

main(argc, argv)
     int argc;
     char *argv[];
{

  enum ptracereq request;

  struct  regs addr;
  int data;
  char *addr2;
  int i=1;
  int pid;

  int tmp;


  if (( pid = fork()) == 0){
    ptrace( PTRACE_TRACEME, 0, 0, 0);
    execl(argv[1],argv[1],0);
    exit(1);
  }
  for(i = 0; i < 100; i++){
    wait((int *)0);
    tmp += sizeof(int);
/*    if(ptrace(PTRACE_POKEDATA,pid,tmp,i) == -1)
      exit(-1);  */



/*    if(ptrace(PTRACE_ATTACH,pid,0,0) == -1)
      exit(-1);   */
    if(ptrace(PTRACE_GETREGS,pid,&addr,i) == -1)
      exit(-1);

    printf("addr.r_pc = %d\n",addr.r_pc);
    printf("addr.r_npc = %u\n",addr.r_npc);
    printf("addr.r_psr = %u\n",addr.r_psr);
    printf("addr.r_y = %u\n",addr.r_y);
    printf("addr.r_g1 = %u\n",addr.r_g1);
    printf("addr.r_g1 = %u\n\n",addr.r_g1);

  }
  /* traced process should resume execution */
  ptrace(PTRACE_CONT, pid, 1, 0);

}  /* end */


Newsgroups: comp.protocols.tcp-ip
Subject: 10BASE-F
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I am looking for documentations or any litrature on the following
subject:

    FIBER OPTIC-BASED HIGH-SPEED LOCAL AREA NETWORK.

Are there any good books or articles on the subject?
Hwo does one go about finding more about the subject?


Please reply by e-mail  to [e-mail]. Thanks

/amiran

Newsgroups: comp.unix.programmer
Subject: Ramdisk
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Organization: Columbia University Department of Computer Science
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Hi all:

    Does anyone out there has any experience, good or bad, reading
and writing to ramdisks. I am trying to speed up the reading from
files and I heard that ramdisk might be the way to go about this. I
would appreciate more details on this scheme -- why it might be
faster, what are the big disadvantage, ... . Also, is it true that one
can only use fopen(), fwrite(), and fread() with ramdisks?


All relevant comments are welcomed.

Pleases respond via e-mail to: [e-mail]

Thanks
/amiran
Newsgroups: sci.math.num-analysis
Subject: An efficient way of finding the the delta of two numbers
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Hi all:

    I am trying to come up with an efficient way (fewest number of
iteration ) to find in a list of numbers (not sorted) two numbers
whose delta (x - y) is the least. So far I could see O(n^2) and
possibly n*log(n). Are there any kind souls out there that know of a
better methods that will improve on the above number of iterations?

    I am not quite sure that this is the most appropriate place to
post this so I apologize head of time for those who resent the question.


Please reply to [e-mail]
Thanks.
/amiran
Newsgroups: comp.unix.questions
Subject: Memory leaks
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Hi all:


    I was wondering if there are any utilities in PD that will
check for memory leaks. Has anyone used such utilities before? If so,
how helpful were they?

Please reply to [e-mail]

Thanks
/amiran