Questions tagged [system-programming]
All questions regarding programming, tweaking and configuring of Unix & Linux core system as a whole or a sub-set of it.
50 questions
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How to pause and resume processing of Keyboard USB on a device, without deauthorizing it?
I am building keyboard multiplexer. My current plan is to connect two devices through Bluetooth, and let my wired USB keyboard switch between these two devices.
My first instinct is to build Two-...
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How to pass a parameter in a command without run the parameter content?
Good days.
I have a little problem.
I have this function in bash script
function denyCheck(){
file=$(readlink -f $(which $(printf "%s\n" "$1")))
if [[ -x $file ]];then
...
- 13
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Does setting TCP_NODELAY disable auto-corking?
Does setting TCP_NODELAY turn off the auto corking behavior? Is there a way to disable it on a per connection basis?
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blkid: blkid_probe_lookup_value() - strange partition types
I need to check filesystem type on a thumb drive in my C++ application. It must be done before mounting a new partition. I also prefer not to call system() function. I tried to use the following test ...
- 23
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My thinkpad is being throttled to 400mhz per core. Is there any way I can force it to clock to normal speeds with the kernel?
there seems to be a common issue with Lenovo ThinkPad and the Intel CPUs being throttled to 400mhz per core:
https://forums.lenovo.com/t5/ThinkPad-L-R-and-SL-series/L380-stuck-on-0-4-GHz-when-loading/...
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Why below code is not able to unblock SIGINT signal
I am trying my hand on Linux Signals. Where I have created a scenario mentioned below:
Initially block all SIGINT signals using sigprocmask().
If sender send SIGUSR1 signal then unblock SIGINT for ...
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How can I make my Linux server sleep and wake on LAN when not in use?
I have recently purchased myself an HP rack server for use as a personal fileserver. This server currently lives under my bed as I have nowhere else to put it. For those not aware (as I was not ...
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What does the STICKY_TIMEOUTS flag for personality(2) do?
Is there a good description of exactly what each of the flags you can pass to personality(2) does? I'm particularly interested in STICKY_TIMEOUTS, but a general detailed description of all of them ...
- 1,412
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883
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Use supercomputer to run a program [closed]
I wrote a c++ program using some libraries called linbox, givaro, gmp.
Now because my computer is to slow I want to run my program on a supercomputer.
I am not very familiar with networks and my ...
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How to programmatically query the Freedesktop application database?
I know about xdg-mime which can query the mapping from MIME filetype to associated desktop application. But this can return mappings to non-existent applications, e.g.
$ xdg-mime default non-...
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How to specify a namespace when creating a tun/tap device?
On linux I can create a new tun/tap device in C using something like:
int fd = open("/dev/net/tun", O_RDWR);
ioctl(fd, TUNSETIFF, (void *)&ifr);
This will create a new network interface in the ...
- 21.9k
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133
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How can I save output of my script to different directory in txt or pdf format [duplicate]
`clear
echo "testing calc"
date
echo -e "======================================"
yc1=0
yc2=0
yc3=0
lol=0
tnd=0
lno=0
c1=0
c1b=0
c2=0
c2b=0
c3=0
c3b=0
bb=12
wt=100
con=768
rip=0
sw=0
echo ""
echo ""
...
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649
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Permission check on profile file in home directory: should it be done?
Say I'm implementing a programming language which has an interactive mode, and that interactive mode reads some ~/.foo_rc file in the user's home directory. The file contains code in that language ...
- 8,897
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458
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How to catch my bluetooth service events
I have usb bluetooth device which is using btusb 0.6 module (driver). The thing is I am interested to know is: how is the systemctl start bluetooth.service event invoked?
I was looking info about ...
- 197
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Loading and execution of programs in memory [closed]
While comparing between linking loader and linkage editor I came across a point that in case of linking loader linking and relocation takes place for each execution of the program( and happens at time ...
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2k
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Low level system call [closed]
C provides library functions such as write(),read().. for system calls.How to make a system call without using any library in linux in C ?
- 379
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System calls in linux
Generally, systems provide a library or API that sits between normal programs and the operating system. On Unix-like systems, that API is usually part of an implementation of the C library (libc), ...
- 379
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5
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3k
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How to set proper monitoring of my services in a automated way? So that if one crash it auto on the fly restarts?
How can i setup monitoring to my system services?
Either using automated script which scan every moment, if httpd, mysqld, and my custom daemon is running or not, if not running it will automatically ...
user11085
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telnet implementation using C [closed]
The program in general is I want to implement telnet program.
On the client side user send its logging name and password, and if it is correct he starts to send commands to the server
On the Server ...
- 317
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2
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717
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Can linux be configured as a server or workstation in DCS and how? [closed]
I am a student of Instrumentation and Control. Considering the versatility and stability of Linux, I was wondering if Linux can be configured to act as a Distributed Control System?
Also if yes, ...
- 115
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1
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888
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Preventing ChromeOS from blanking the screen when working on a different tty
I am running Archlinux in a chroot alongside Chrome OS on a chromebook. The original project is there, my fork of it is here (mostly similar).
The issue is that the display power management of Chrome ...
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How to find the header file where a c function is defined?
Is there an easy way to find out which header file a C function declaration is in? cding into /usr/include and running (grep -E 'system.*\(' *.h -R) works with some trial and error, but isn't there an ...
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Cursor movement in terminals
I'm trying to wrap my head how shells move the screen cursor around (Moving around input the arrow keys and such).
I've been doing a lot of testing, and I haven't found any system call that allows ...
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2
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8k
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Learn Linux System Programming by doing projects [closed]
I have only a very basic idea about linux system programming. I have not done any real projects using linux system programming. In my current company I do system admin type work, but I am more ...
- 211
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196
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SDK for Developer
Is there any SDK for developers under Linux? I mean more than man pages, it would be more like MSDN Library or Windows SDK under windows, where all documentation about programming and developer guide ...
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