sys_datacopy in Minix Post: 302169384

Sponsored Content

Top Forums UNIX for Advanced & Expert Users sys_datacopy in Minix Post 302169384 by pedrosacosta on Thursday 21st of February 2008 05:31:48 AM

02-21-2008

Registered User

sys_datacopy in Minix

I'm writing a program that must log all the kernel calls existing in Minix. I recall that Minix is a microkernel OS.

I've a user process that pass a char* that points to a buffer memory to the kernel level. In the kernel level I get all the information, and now, I would like to copy the info to the buffer passed by the user. How can I do that?

Since kernel and user process are in different address space, I use the sys_datacopy function that should do it.

The problem is that, in the user level, that buffer prints me (null).

the function that I use is:

sys_datacopy(SELF,
(vir_bytes) buf,
who, /* <---- I suppose that this in points to the user process number */
(vir_bytes) m_in.m1_p1);

m_in is a structure of type message, a structure that Minix uses to pass info from the kernel to the user level and otherwise.

m1_p1 is a char* variable.

You can find it more info about the structure in ipc.h.

Thanks,
Pedro

pedrosacosta

View Public Profile for pedrosacosta

Find all posts by pedrosacosta

7 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

Minix Installation

hi, I'm trying to install Minix 2.0.3 on an old gateway2000 4dz2-66 manufactured back in 1995. After I ran 'part' in setup, It make the root/swap/usr subpartitions and then I get this message: installboot: No such File or Directory This was when i had my /usr disk in,here is teh output i...

2. Solaris

Help with minix

hey guys i hope there is someone familiar with minix that can help me. Well, the problem i am sitting with is that a ran a program with an infinite loop in it, now i think i ran out of memory in the root because a keep on getting the message " no space on the root device 3/128 ", whenever i try...

3. Shell Programming and Scripting

Api Posix in Minix

Hi, I'm using minix and I don't know how to use API POSIX (I've read ipc.h :confused:), someone could help me? Thank you :)

4. Shell Programming and Scripting

File system in MINIX

Hi I am new in MINIX I want to add data into inode and retrive. where I add these information and how I can retrive? Thanx Rose

5. Programming

Minix help wanted

Hi to all, i am trying to make a kernel call that will display the number of times each kernel call was called. Any idea where to look? I can't find the right files and also how to get all those values. Already made a kernel call that displays how many kernel calls are in the system. I am using...

6. Homework & Coursework Questions

Noob minix problem

please help!! The question that has been asked is to use /tmp directory in minix to get to know the root password or get the root privilege . onr thing that I have done is : % cp /bin/sh /tmp % chmod 4777 /tmp/sh now what next must i do to get the root privelege? or maybe some other method ...

7. UNIX for Dummies Questions & Answers

Recycle bin on minix 3.2.1?

Hi. I'm started to use minix 3.2.1 recently and I'm trying to create a recycle bin for it. I'm kinda struggling on how to do it. I searched internet and I found scripts created for it but I actually didn't learn how to create scripts in college and I'm not sure if I understand them. I just wanted...

LEARN ABOUT MINIX

s_n_d

SET_NET_DEFAULT(8)					      System Manager's Manual						SET_NET_DEFAULT(8)

NAME

       s_n_d, set_net_default - select the default TCP/IP network

SYNOPSIS

       set_net_default: not found

DESCRIPTION

       This  manual page is here because so many others refer to it.  The set_net_default command does not exist under standard Minix, because the
       TCP/IP server only supports one network.  The server under Minix-vmd supports four different networks, that  can  each  be  chosen  as  the
       default network.

       The  TCP/IP library and commands do have a notion about a "default network" however, because the code is shared between the Minix versions.
       So if you want to venture into network programming then you should know about the devices and environment variables mentioned below to make
       your program compatible.  (Especially since there is a plan to upgrade the TCP/IP server for standard Minix.)

   Options and environment to change the default
       Many  TCP/IP  programs implement the following options and environment variables to change the default devices set by set_net_default.  The
       options are only implemented for low level programs where it makes sense to name a network device.  The environment variables are  used	in
       all code.  You can run a process and all its children connected to a different network by setting four environment variables.

       ETH_DEVICE=device
       -E device
	      Device to use as raw ethernet device instead of the default /dev/eth.

       PSIP_DEVICE=device
       -P device
	      Pseudo IP device to use instead of /dev/psip.

       IP_DEVICE=device
       -I device
	      IP device to use instead of /dev/ip.

       TCP_DEVICE=device
       -T device
	      TCP device to use.

       UDP_DEVICE=device
       -U device
	      UDP device to use.

FILES

       /dev/eth[01]	 First and second raw ethernet.

       /dev/psip[01]	 First and second Pseudo IP network.

       /dev/ip[0123]	 IP devices for two ethernets and two Pseudo IP networks.

       /dev/tcp[0123]	 TCP devices for same four networks.

       /dev/udp[0123]	 UDP devices.

       /dev/eth, /dev/psip, /dev/ip, /dev/tcp, /dev/udp
			 Devices  for  the default network, links to the devices above.  Eth is only present if ethernet is the default, psip only
			 for pseudo IP.

SEE ALSO

       ip(4), boot(8).

AUTHOR

       Kees J. Bot (kjb@cs.vu.nl)

																SET_NET_DEFAULT(8)