$ gdb a.out
...
(gdb) run
Program received signal SIGSEGV, Segmentation fault.
0xff3b0878 in memset () from /usr/platform/SUNW,Sun-Fire-V240/lib/libc_psr.so.1
(gdb) bt
#0 0xff3b0878 in memset () from /usr/platform/SUNW,Sun-Fire-V240/lib/libc_psr.so.1
#1 0xff1de7d4 in sema_init () from /usr/lib/libthread.so.1
#2 0x0003db28 in initializeSemaphores () at t.cxx:82
#3 0x0003dbe4 in main () at t.cxx:92
(gdb) list
81 {
82 sema_init(&(Semaphores->mutex),1,USYNC_PROCESS,NULL);
83 sema_init(&(Semaphores->barber),0,USYNC_PROCESS,NULL);
(gdb) p Semaphores
$1 = (semaphores *) 0x0
(gdb) quit
Dear Reader,
I'm in a multiprocess environment working with shared mem and semaphores as mutex.. The problem is -- If one of the process hooked up with the semaphore and accessing the shared mem, terminates abruptly ( or got killed ), other process which are in want of the semaphore are... (1 Reply)
Hi all,
I am using HP 10.20 on A 9000/785. My question is:
If I am the only person logged in as root at the moment, how many "semaphore proccesses" should I have?? Is it only one, or it is relevant to other system proccesses?
Here is what I get listing the current semaphores
# ipcs -sp... (1 Reply)
Hi there,
Could someone please confirm which POSIX semaphore routines should be used for a multiprocess (and not multithreaded) environment?
sys/sem.h definitely works. but the routines, semget, semctl, semop are pretty unwieldy. So, I am looking for an easier way out.
From the man pages... (2 Replies)
Hi Friends,
If i execute this command it comes back with 300 lines:
ipcs|grep cerebrus >>> i would like to clear the semaphores but ipcrm can remove one id at a time. is there a quicker way of removing semaphores maybe using awk?
Regards, (1 Reply)
been searching around on how to use an up and down function with semaphores but i can't find an example. i looked into using: "semop" but i have no idea how to use it. I have been able to declared the semaphores using semget and initializing them using semctl. (7 Replies)
Hello, first of all I apologize if this thread is not in the correct section of this forum, but this one just seemed the most appropriate.
The question I have does not concern Unix specifically, it applies to virtually any OS, however it is in Unix where I learned about this problem.
So, the... (8 Replies)
I am having problem with semaphores. I am trying to protect line where process prints so that every process with print in proper order.This is the code..
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/types.h>
union... (3 Replies)
Hello Everybody,
I am building a server. this server contains some data. Clients may modify this data or read this data.
If a client is reading the data and at the same time another client is modifying the data then at this case the reading client may read some false data (some old mixed with... (1 Reply)
Hi everybody, :o
I hope you can help me to solve this problem I have.
I'm trying to write a program with Linux in C which uses semaphores and shared memory. In particular I need to create a leader process and three more processes "calculators" (1, 2 and 3) that make mathematical operations.... (4 Replies)
Discussion started by: IgorGest
4 Replies
LEARN ABOUT MINIX
gzexe
GZEXE(1) General Commands Manual GZEXE(1)NAME
gzexe - compress executable files in place
SYNOPSIS
gzexe name ...
DESCRIPTION
The gzexe utility allows you to compress executables in place and have them automatically uncompress and execute when you run them (at a
penalty in performance). For example if you execute ``gzexe /usr/bin/gdb'' it will create the following two files:
-rwxr-xr-x 1 root root 1026675 Jun 7 13:53 /usr/bin/gdb
-rwxr-xr-x 1 root root 2304524 May 30 13:02 /usr/bin/gdb~
/usr/bin/gdb~ is the original file and /usr/bin/gdb is the self-uncompressing executable file. You can remove /usr/bin/gdb~ once you are
sure that /usr/bin/gdb works properly.
This utility is most useful on systems with very small disks.
OPTIONS -d Decompress the given executables instead of compressing them.
SEE ALSO gzip(1), znew(1), zmore(1), zcmp(1), zforce(1)CAVEATS
The compressed executable is a shell script. This may create some security holes. In particular, the compressed executable relies on the
PATH environment variable to find gzip and some standard utilities (basename, chmod, ln, mkdir, mktemp, rm, sleep, and tail).
BUGS
gzexe attempts to retain the original file attributes on the compressed executable, but you may have to fix them manually in some cases,
using chmod or chown.
GZEXE(1)