General :: Can't Statically Decide Virtual Address Of The Function At Compile Time?
Feb 8, 2010
I have read a couple of articles on how dynamic linking works (those stuff about got, plt and lazy binding), and I am still not sure why you need to do dynamic linking in such a complicated way.Suppose your program uses a function in a shared library that needs to be linked dynamically at run time (like a printf). Why can't you statically decide the virtual address of the function at compile time? After all, all you need to do is to enter the page table entry corresponding to the address of the function if the library has been already loaded to a physical page frame.
I am trying to compile the iputils package on FC12 statically but badly stuck up on a below error. My requirement is; I need to have ping utility built statically.
Any clue whats missing here? Per my understanding its trying to locate the glibc and when I search for glibc rpm I can see all those packages are properly installed.
In my college many proxy : port (like 144.16.192.245:8080)are using to get Internet connection, performance of each proxy changes, how can i decide which one is working well at particular time. is there any way to switch over them automatically?
I manage to use the function "time" and "localtime" in gcc.But while I used it in a module in kernel space the above 2 functions are giving error.Even in kernel space time.h header file is not identified. tell the similar time function which can be used in kernel space
I am using Debian linux. I have 100 timers running. If a timer expired which will generate a signal and it was mapped to a same function handler. All the timers are mapped to one function handler. The problem is if the timer expires one at a time, the function handler called at a time. But if the 2 timers expires at a time, the function handler is called one time only instead 2 times. Is it possible to invoke the function handler as many times based on timer expirary happens simultaneoulsy?
When I create virtual ethernet interface and do a ping -I <v_int> <host> the outgoing address is the one of the physical interface and NOT the virtual interface.Is there no chance that trafic will go out with virtual interface address??Incoming trafic is done well i.e. responds to the virtual interface have the virtual address.
My problem is that I have 2 modems and want to check both default gw behind the modems. If I do a "normal" ping both are reachable over default route even the modem which is not the default route will not work because ping goes over the working modem.So I have 2 routing tables and want to route the virtual interface to one modem the other to the other modem
I need a small shell based program that prints the mac address of physical ethernet adapter from it's firmware. I need this utility for license generation and appliance activation. I have tried several example but none of them is flawless, The easiest method I have found is to parse the output of "ifconfig" command but it has also some drawbacks.
1. Firstly program should differentiate between physical and virtual adapters. Physical means installed on board(wired or wireless) or installed additionally. Virtual adapters are those created by VPN or created by virtualization apps such as VirtualBox/VMWare etc. I am not interested in virtual ones.
2. In case of more them one physical adapters(wired and wireless), it should print the mac address and description(name & vendor) of both/all adapters.
3. If media is disconnected then also it should be able to read the mac address and description(name, vendor) of card.
4. This one is bit complex. I know that 'ethtool' can show you the universal mac address but it's limited to use only 2 types of drivers and won't work in all cases.
I have millions of small chunks of new's and delete's in my program. Even though no memory leak is detected through valgrind or purify, memory grows. But the growth is degrading over the number of times of the execution of the tasks. Can i think that fragmentation plays a role in this?
A process is trying one access to memory, for example through an array (ex.: vect[0]=123. What happens?
Here below what I guess but I'm not sure and accept any comment (please, distinguish between "the system" and "the CPU" in case).
Let's suppose swapping to disk disbled.
We have two scenarios: without and with cache.
If no cache is present in the system: 1. The CPU must discover the phys addr of vect[0] virtual addr. To do that, has to read from 3 (or 2 depending on the system?) pages tables, stored in memory as well. 2. The CPU writes to the final address.
These mean 4 memory accesses.
If cache is present: 1. Like above but, if the pages tables are in cache, we have 3 accesses to that. 2. If the req. page is not in cache, it's reads from ram and transferred to it. Afterwards, cache is written. In the best case we have 4 cache accesses.
I setup a virtual server with these configurations:
1. Mail server: POSTFIX / DOVECOT 2. Webmin / Virtualmin
I am getting email to desired folders locally but I am not getting email from outside to desired users. Emails are bounced back with message "Address not found in virtual alias table".
Recent log errors are:
Sep 8 04:25:49 server1 postfix/smtpd[28002]: cannot load Certificate Authority data Sep 8 04:25:49 server1 postfix/smtpd[28002]: warning: TLS library problem: 28002:error:02001002:system library:fopen:No such file or directory:bss_file.c:122:fopen('/etc/pki/postfix/root.crt','r'):
As i undertsand - out of 1GB of the virtual Address space for Kernel from 3GB to 4GB of the process address space, Kernel image (code, data, bss, stack, heap) resides staring @0x0 address. Vmalloc area starts either at the end of Physical ram size or at 896M. This 896M cap is mandated to ensure that minimum of 128MB is reserved as vmalloc_reserve for vmalloc,kmap etc.
Is the understanding correct? Now trying to map Physical Zones into this 1GB address space
Initial 16MB is mapped to ZONE_DMA 16MB - 896MB is mapped to ZONE_NORMAL 896MB - 1024MB is mapped to ZONE_HIGHMEM
Does this mean that Kernel image is residing in ZONE_DMA area? Any call to vmalloc() in kernel code will return address beyond 896M? insmod of any LKM will internally invoke vmalloc() to obtain contiguous area - where will this code physically located along with rest of kernel code in ZONE_DMA or in ZONE_HIGHMEM?
I am trying to install vmware server on CentOS: In vmware installation guide it says before intalling:
Before you begin, read the following notes and make adjustments to your host system: The realtime clock function must be compiled in your Linux kernel. The parallel port PCstyle hardware option (CONFIG_PARPORT_PC) must be built and loaded as a kernel module (that is, it must be set to m when the kernel is compiled).
I am in verse to test "Multicast Packet filtering".I want to setup Virtual Machines to be servers with bind option set to a multicast group address of 225.0.62.87.Then I want to configure the client VM, connecting to the multicast group address and setting the TTL as needed.
I've had Ubuntu (8.10) on my netbook in the past and I really liked it. I'm currently running Fedora and feeling like I should "change it up" again. I've played around with Ubuntu 10.04 Lucid a little, and so far I'm very impressed. I've always wanted to try Arch, but I'm worried I won't have the driver support I need for all the non-standard hardware in a netbook.
Does anybody have a suggestion for a new distro to try? I'm preferably looking for something feature-rich over light-weight, and something that I can have up and running with a minimum of configuration (at least partially working).
I've been trying out various variants of Ubuntu (Ubuntu, Kubuntu, Xubuntu, Linux Mint, Ultimate Ubuntu, to be specific) as well as the latest Fedora. The only thing that I can distinguish between the various distributions is the desktop environment that it uses (but some distributions, like Fedora, have multiple versions) and the software packages it comes with. But sofware can always be installed afterwards, and so can desktop environments, so what varies between the various distribution branches on a deeper level, on the things that the newbie user like me can't directly see? And is there any easy way to compile my own version of Linux?
I have set 'ONBOOT=no' in interface script '/etc/sysconfig/network-scripts/ifcfg-eth0:2' but my interface bring up at boot time, what is the problem , I have checked it 3 or 4 diff os/machine but the same issue. Can anyone please help me to disable virtual IP's at boot time that network script make it up every boot time.
How does Compiz automatically decide which windows should be sticky (i.e. should be visible on all workspaces)? Windows such as gnome-panel and cairo-dock always stay on the visible workspace, without requiring additional configuration. How does Compiz figure this out?
When I try to write email, and enter the first few letters of the recipient in the "to:" box, it sometimes but not always autocompletes. i.e., let's say my contact's name is Frederick, his address is e.g. robertsharry@snotmail.com. I enter Fred or fred or fre, a couple of addresses come in to the autocomplete drop-down, but not his. After searching all over over to find his address by other means, I start to write it in manually only to find that he IS in my address book (and also in recent addresses), listed under Freddie. I know that the word Freddie is not in his actual address, but what is the point of having a search function if you have to remember the address yourself? In other words surely the drop down search should show display names (as well as any other fields)?
I am writing a game in C with SDL. I can successfully display one image on the screen and animate it. However, I am having a lot of issues getting the background to display using the same method. I was asking for help on SDL related forums, but I determined that the issue is not SDL related, and it is actually a pointer issue. However, I can't find where I'm going wrong.
I am only getting 4.7kb/s, dispite there being 31 or so Seeders. The port is just opening and closing it seems, I have no idea why though.The port was opened both with firestarter (which isn't supposed to be firewalling ATM) and "sudo iptables -A INPUT -p tcp --dport 6884 -j ACCEPT".It was also opened under the 'Application Sharing' menu of my router.
I am using malloc and frees a lot in my program. It shows its allocated but when i remove it doesnt show as the memory is removed(I am using the top command to view VIRT memory usage). If this continously grows what would happen to my program (Will it go out of memory?)
I'm running 9.10. I was installing ALSA so that I could run my EMU 1616, and when I tried to go through the steps to install, I'm running into two errors that I've noticed so far. I think. Anyway, the first is that is states that the panelw library isn't there, and that alsamixer: function snd_ctl_open failed for default: No such device or address. The alsamixer one is really odd, since it's there, but I don't know why it won't run.
I initially had it running, and now it isn't. I've yet to get sound out of my EMU. the terminal window also tells me that it can't find the snd_emu file, even though it exists on the computer as well. I need an answer for a dummy.
