10 More Discussions You Might Find Interesting
1. How to Post in the The UNIX and Linux Forums
Hi All,
Please help me and guide me to write a bash/shell script on Linux box to delete parent entry with all their child entries.
example:
Parent is :
----------
dn: email=yogesh.kumar@wipro.com, o=wipro, o=in
child is:
----------
dn: cn: yogesh kumar, email=yogesh.kumar@wipro.com,... (1 Reply)
Discussion started by: Chand
1 Replies
2. Programming
Hello to all
I want download a file in osx intel 64 with NASM , I want to use socket syscall
This is part of my code
section .data
command db "GET /test/2.gif HTTP/1.1\r\nHost: 10.1.1.187\r\n\r\n", 0
; url db "http://172.16.207.153/test/2.gif", 0
global main... (1 Reply)
Discussion started by: recher.jack
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3. UNIX for Advanced & Expert Users
Hello Experts,
If a Solaris process is calling some syscall, and right now execution is inside syscall doing only CPU work, for example the inside simplest times syscall,
-> app_func
=> times
<< we are here now, we have entered in the times, but not exited yet
<= times
<- app_func... (9 Replies)
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4. SCO
Hello,
is there any command in SCO unix by which I can check if the file system is HTFS or DTFS?
Thanks (1 Reply)
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5. UNIX for Dummies Questions & Answers
I saw somewhere that describe read() as a primitive. But when I lean signals, it says the read() may be interrupted by a signal.
My Question:
1, What is the diffence between primitive and reentrant?
2, Is read() a primitive or reentrant?
3, Are all system calls primitive or reentrant? (2 Replies)
Discussion started by: vistastar
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6. Programming
Hi all,
i just started started learning system programming and want to pursue a career in the sys prog area.
below is the program that use a fork() call.
i read in one of the tutorials that parent process and child process uses different address spaces and runs concurrently.
that meas each... (2 Replies)
Discussion started by: MrUser
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7. Programming
I am working on solaris 9. and use gmake to compile and linke c/c++ program.
anybody can tell me the distinguish between gmake and make? :confused: (10 Replies)
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8. HP-UX
how to distinguish different files and choose a mode while ftp?means which modes ascii or binary for zip(.gz) ,.txt,.sh,.dat and executable as well as movie files. (1 Reply)
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9. Programming
I have a question regarding the recv syscall.
Suppose I have a client/server and the following exchange of message took place:
Client --> Server using multiple send syscalls one after another immediately:
send "Packet1"
send "Packet2"
send "Packet3"
Server receives in the... (2 Replies)
Discussion started by: heljy
2 Replies
10. AIX
Hello,
In a script shell, I have a variable containing the name of a file and I would like to distinguish the name from the extention of the file. For example, the file 'myfile.txt' is in a variable called $VAR. How can I obtain 2 variables, one with 'myfile' and the other with 'txt' ?
Thank you (2 Replies)
Discussion started by: tbeghain
2 Replies
ptrace(3C) Standard C Library Functions ptrace(3C)
NAME
ptrace - allows a parent process to control the execution of a child process
SYNOPSIS
#include <unistd.h>
#include <sys/types.h>
int ptrace(int request, pid_t pid, int addr, int data);
DESCRIPTION
The ptrace() function allows a parent process to control the execution of a child process. Its primary use is for the implementation of
breakpoint debugging. The child process behaves normally until it encounters a signal (see signal.h(3HEAD)), at which time it enters a
stopped state and its parent is notified by the wait(3C) function. When the child is in the stopped state, its parent can examine and mod-
ify its "core image" using ptrace(). Also, the parent can cause the child either to terminate or continue, with the possibility of ignoring
the signal that caused it to stop.
The request argument determines the action to be taken by ptrace() and is one of the following:
0 This request must be issued by the child process if it is to be traced by its parent. It turns on the child's trace flag that
stipulates that the child should be left in a stopped state on receipt of a signal rather than the state specified by func (see
signal(3C)). The pid, addr, and data arguments are ignored, and a return value is not defined for this request. Peculiar results
ensue if the parent does not expect to trace the child.
The remainder of the requests can only be used by the parent process. For each, pid is the process ID of the child. The child must be in a
stopped state before these requests are made.
1, 2 With these requests, the word at location addr in the address space of the child is returned to the parent process. If instruction
and data space are separated, request 1 returns a word from instruction space, and request 2 returns a word from data space. If
instruction and data space are not separated, either request 1 or request 2 may be used with equal results. The data argument is
ignored. These two requests fail if addr is not the start address of a word, in which case -1 is returned to the parent process
and the parent's errno is set to EIO.
3 With this request, the word at location addr in the child's user area in the system's address space (see <sys/user.h>) is returned
to the parent process. The data argument is ignored. This request fails if addr is not the start address of a word or is outside
the user area, in which case -1 is returned to the parent process and the parent's errno is set to EIO.
4, 5 With these requests, the value given by the data argument is written into the address space of the child at location addr. If
instruction and data space are separated, request 4 writes a word into instruction space, and request 5 writes a word into data
space. If instruction and data space are not separated, either request 4 or request 5 may be used with equal results. On success,
the value written into the address space of the child is returned to the parent. These two requests fail if addr is not the start
address of a word. On failure -1 is returned to the parent process and the parent's errno is set to EIO.
6 With this request, a few entries in the child's user area can be written. data gives the value that is to be written and addr is
the location of the entry. The few entries that can be written are the general registers and the condition codes of the Processor
Status Word.
7 This request causes the child to resume execution. If the data argument is 0, all pending signals including the one that caused
the child to stop are canceled before it resumes execution. If the data argument is a valid signal number, the child resumes exe-
cution as if it had incurred that signal, and any other pending signals are canceled. The addr argument must be equal to 1 for
this request. On success, the value of data is returned to the parent. This request fails if data is not 0 or a valid signal num-
ber, in which case -1 is returned to the parent process and the parent's errno is set to EIO.
8 This request causes the child to terminate with the same consequences as exit(2).
9 This request sets the trace bit in the Processor Status Word of the child and then executes the same steps as listed above for
request 7. The trace bit causes an interrupt on completion of one machine instruction. This effectively allows single stepping of
the child.
To forestall possible fraud, ptrace() inhibits the set-user-ID facility on subsequent calls to one of the exec family of functions (see
exec(2)). If a traced process calls one of these functions, it stops before executing the first instruction of the new image showing signal
SIGTRAP.
ERRORS
The ptrace() function will fail if:
EIO The request argument is an illegal number.
EPERM The calling process does not have appropriate privileges to control the calling process. See proc(4).
ESRCH The pid argument identifies a child that does not exist or has not executed a ptrace() call with request 0.
USAGE
The ptrace() function is available only with the 32-bit version of libc(3LIB). It is not available with the 64-bit version of this library.
The /proc debugging interfaces should be used instead of ptrace(), which provides quite limited debugger support and is itself implemented
using the /proc interfaces. There is no actual ptrace() system call in the kernel. See proc(4) for descriptions of the /proc debugging
interfaces.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |MT-Safe |
+-----------------------------+-----------------------------+
SEE ALSO
exec(2), exit(2), libc(3LIB), signal(3C), signal.h(3HEAD), wait(3C), proc(4), attributes(5)
SunOS 5.10 22 Mar 2004 ptrace(3C)