I have made a C program, compiled with gcc , combined with some bash scripts, for playing music using mpd/mpc from web & usb.
It works well.
But at times the program exits after a while with
xxxx segmentation fault
where xxxx is a 4 digit number.
Can someone tell me what this means & how to fix it ?
Thanks !
Edited: The number before the message is random, so replaced with xxxx
I found the cause of the problem, after reading through my code.
There was an external program I was calling regularly by means of the 'popen' function.
But I forgot to add the corresponding 'pclose' function !
So, after some time there were too many files open, and my application was terminated.
After doing the correction, I left my application running overnight, and in the morning, it was still running !.
This was the longest it had run without crashing.
So I believe that was the source of the problem.
Edit: its been 24 Hrs that my application has been running without crashing, so I'l have to mark this as the answer.
Related
I tried Brave on Mac with the command in the answer by K J in the following question. But after running many such conversions, I may end up with a message of -bash: fork: retry: Resource temporarily unavailable in a terminal. It seems that too many threads are used and not cleaned afterward. What is going wrong here?
How to use brave to automate printing html to pdf?
Ok I guess this may not be normal type of answer as its kind of "works for me"
In cases such as this where the "programming" is simply one cross platform command, that in its dependencies uses system and application resources, there are times one user has problems and others do not. Thus debugging can be highly system dependent.
By way of explanation as to potential issues (and its too long for simple comments) here are my experiences on Windows.
pre running (why so many windows processes !!)
Fresh boot
Apps=3
one is system folder explorer
one is this notepad
one is task manager monitor
Background processes=82 Including Edge (inactive=5 !!)
processes=107 including console = 5 !!
Start command terminal
Apps =+1 with 3 sub processes ?
Background =+1 command prompt
processes =+1 (console now = 6)
Start Brave portable
apps =+1 Brave no page requested only welcome but with 8 sub processes !#?
background =+1 brave portable
processes =same (console still = 6)
Navigate to this page
apps = same Brave with this page requested = 9 then drops back to 8 sub processes !
background = same 1 brave portable
processes =same (console still = 6)
Run 20 similar commands with/without --enable-logging
Mea Culpa (Idiot) 20 fails several times because I did not verify if will run without a running Brave nor test bad cut and paste
but looks like no residual change to processes ??
Try again with brave closed
Apps and Background processes returns to before Brave active
for /l %a in (1,1,20) do brave-portable --headless --print-to-pdf="C:\Users\K\Downloads\brave-portable\test2-%a.pdf" --disable-extensions --print-to-pdf-no-header --disable-popup-blocking --run-all-compositor-stages-before-draw --disable-checker-imaging "https://stackoverflow.com/questions/74788259/how-to-use-brave-to-automate-printing-html-to-pdf"
Hmmm without error checking there is some noticed difference to an earlier run
call completes in a few seconds thus its much too quick to see tasks listed in manager.
Background processes ramped up to 194 !! before drop back to about 78
and after about 20 seconds there are 19 same size files (as almost might be expected)
Now what is odd about that is that usually from experience they should all be different sizes as each call should show different in-page adverts over time
but then again I had logged in and accepted cookies earlier, so there should be no ads to make a difference in later runs.
EXCEPT ONE rogue file out of 20 has an advert Arghhhhhhhh!!
so the inconsistencies saga continues.
However there is no residual use of task processes in my Windows portable Brave with that command sequence!
On its own Brave is using only a few percent of CPU and Memory before and after with no hint of tying up disk or other resource features.
Let me start off with the components used:
GPIO extension board to connect the raspberry pi to components
Bme280
Pi 3B
Problem description:
This problem was intermittent at first. We were receiving reading and the error occured out of nowhere, made adjustment to the sensor(taking out and putting it back in) which solved it but when we touch the sensor the error showed up again.
We decided to change the sensor and the problem turned from intermittent to persistent. Now we have this as permanent issue.
We removed the package for BME280 and SmBus2 and decided to reinstall it again.
RPI Bme280: https://pypi.org/project/RPi.bme280/
I followed this BME280 installation guide, however when prompting for 'i2cdetect -y 1' there were lines but no number showing up.
What has been confirmed so far:
Patching up of circuits was fine, tested with my lecturer pi and it
works fine.
Codes is fine, we even use the sample code provided by RPi.bme280
I2c was enabled everytime
Please help me because I am really lost. I needa submit this by next week so any help is appreciated.
Problem pic --> Picture of the problem
I've tried to respond, but there is a few pitfalls in SMBus and i2c, so to break the question into smaller bits I've quoted your original message with an indent. The response is provided beneath.
This problem was intermittent at first. We were receiving reading and the error occurred out of nowhere, made adjustment to the sensor(taking out and putting it back in) which solved it but when we touch the sensor the error showed up again.
I locked onto the statement, "Touched the sensor". Is there a chance the BME280 experienced an ESD discharge? And therefore is now partially or fully broken?
Are you using an ESD safe room? or at least ESD bracelet. You will not notice small ESD discharges, and for small electronics even a sub 1000V discharge can cause damage instantly or over time. (Fundamentals of Electrostatic Discarge - incompliancemag.com)
I followed this BME280 installation guide, however when prompting for 'i2cdetect -y 1' there were lines but no number showing up.
The I2Cdetect -y 1
Will send a ReadBit message to each possible slave 0-127. Then listens for the ACK on the slave address.
The message is very simple, but does the trick for detecting working i2c slaves.
As you stated there is no "Lines", i would suggest the slave either has issues responding, if the BME280 has the correct 3v3+GND supplied.
As another possability, could you redo this step dtparam=i2c_arm=on,i2c_baudrate=400000
(Set the baudrate way down to 10000 /10k. Should this solve the issue and you need higher bandwidth, attempt on "50000 /50k" or "100000 /100k") This is just to eliminate the possibility the slave cannot opperate on this high frequency. 400k Baudrate for SMBus is high for a prototype/testing scenario. Very small amounts of interference can corrupt the data over SDA.
Another possibility is the Sink-Current which i've learned the hard way is not the same on i2c and SMBus over i2c.
Is you Pull-up resistor appropriate for the limited sink-current?
The SMBus specifies a minimum sink current of 100µA, and a maximum of 350µA, compared to 3mA for the I²C bus (Ampere=Voltage/Resistance Ohm).
Now to the Software issue.
From your supplied picture on imgur.
File "newcodes_''''''''''''''.py" line 2, in
Your compiler cannot find "bme" where you attempt to import bme280. Reference/path issue?
This can be the cause for other issues further into the code calls.
I don't know what SW you are writing the code in, but if there is an option to insert a breakpoint and run a debug build. I would suggest starting there :)
Alright I have resolved the issue, I changed the wire from jumper wire to hard wire. Thank you guys for your response. I appreciate all of them :D
My MacBook spontaneously wakes up from sleep mode with high fan activity.
I want to do a investigate this in RTC or power settings? Or by strace-ing of processes, etc (using some process/kernel magic!).
Hint: It is probably managed by "rtcwake".
I am not even sure if this is a scheduled task, or from a WiFi wakeup, or something else.
I don't want guesses about what usually causes this in Mojave, etc. Instead:
I need to do a systematic investigation on this on my MacOS (Mojave). Linux-related answers are also appreciated.
This is about system standby, sleep-mode, suspended mode. (Note that this is not about standup and wakeup of individual processes. The whole laptop turns on spontaneously.)
Reading the log file is the best way to debug the problem.
So, try this command in your Terminal to fetch the system logs,
this will tell you "wake up" history.
log show --style syslog | fgrep "Wake reason: EC.LidOpen"
To see the wake reason:
For macOS Sierra, Mojave, Catalina, and newer
log show |grep -i "Wake reason"
Or for MacOS El Capitan, Yosemite, Mavericks, and older
syslog |grep -i "Wake reason"
This will look like:
MacBookPro kernel[0] : Wake reason = OHC1
MacBookPro kernel[0] : Wake reason = PWRB
MacBookPro kernel[0] : Wake reason = EHC2
MacBookPro kernel[0] : Wake reason = OHC1
So what do these wake reason codes mean?
OHC: stands for Open Host Controller, is usually USB or Firewire. If you see OHC1 or OHC2 it is almost certainly an external USB keyboard or mouse that has woken up the machine.
EHC: standing for Enhanced Host Controller, is another USB interface, but can also be wireless devices and bluetooth since they are also on the USB bus of a Mac.
USB: a USB device woke the machine up
LID0: this is literally the lid of your MacBook or MacBook Pro when you open the lid the machine wakes up from sleep.
PWRB: PWRB stands for Power Button, which is the physical power button on your Mac
RTC: Real Time Clock Alarm, is generally from wake-on-demand services like when you schedule sleep and wake on a Mac via the Energy Saver control panel. It can also be from launchd setting, user applications, backups, and other scheduled events.
There may be some other codes (like PCI, GEGE, etc) but the above are the ones that most people will encounter in the system logs. Once you find out these codes, you can really narrow down what is causing your Mac to wake up from sleep seemingly at random.
Hope this will help :)
This answer is based on Linux, so it might not apply strictly to Mac.
To determine whether rtcwake is responsible for your MacOS wakeups, you could replace the executable (in my Ubutnu it is /usr/sbin/rtcwake) with a wrapper script that leaves a sign of rtcwake having run, e.g.
$ cd /usr/sbin/rtcwake
$ sudo mv rtcwake rtcwake_orig
and then write script /usr/sbin/rtcwake containing
#!/bin/bash
touch $HOME/rtcwake_ran
/usr/sbin/rtcwake_orig
Variants of the script would depend on your shell.
In particular, in the last line you would possibly run rtcwake in some alternative way, so as to not own the process (nohup / disown).
See https://unix.stackexchange.com/questions/152310/how-to-correctly-start-an-application-from-a-shell
To inspect possible causes of wakeup, you can check various relevant logs, at /var/log.
E.g., syslog*, acpi*.
See also https://unix.stackexchange.com/questions/83036/where-is-the-log-for-acpi-events
Do you have wakeonlan?
Here I am documenting my systematic approach. It is loosely based on, and initiated by, the answer by #vijay-rajpurohit, which is in turn based on comment by #Robert #1431720 . Note that the final result is particular to my MacOS machine, based on the logs shown below. It will be different in your MacOS.
In first attempt, I first checked the logs using: log show --style syslog | grep ... but it is taking too long. I accidentally checked /var/log/wifi.log after exploring the /var/log/ (I am also curious about /var/log/powermanagement/*.asl).
This turned out to be most useful:
cat /var/log/wifi.log|grep -i "Wake reason"
Then found this line: (note the EC. bit)
Thu Apr 23 22:41:32.359 Info: <airportd[219]> _systemWokenByWiFi: System wake reason: <EC.ARPT>, was woken by WiFi
Then googled for EC.ARPT, I found the following commands:
pmset -g log Useful stats about "Total Sleep/Wakes since boot".
pmset -g assertions This turned out to show the full answer to this question:
2020-04-24 02:23:38 +0100
Assertion status system-wide:
BackgroundTask 1
ApplePushServiceTask 0
UserIsActive 1
PreventUserIdleDisplaySleep 0
PreventSystemSleep 0
ExternalMedia 0
PreventUserIdleSystemSleep 0
NetworkClientActive 0
Listed by owning process:
pid 111(hidd): [0x0000200a000986a9] 00:00:00 UserIsActive named: "com.apple.iohideventsystem.queue.tickle.4295010950.3"
pid 85(apsd): [0x0003b830000b90bd] 00:00:10 ApplePushServiceTask named: "com.apple.apsd-waitingformessages-push.apple.com"
Kernel Assertions: 0x100=MAGICWAKE
id=504 level=255 0x100=MAGICWAKE mod=24/04/2020, 01:57 description=en0 owner=en0
Idle sleep preventers: IODisplayWrangler
In short, in a systematic approach, I explored the following keywords based on the logs, and googled each :
EC.ARPT (example link)
iohideventsystem (example link)
MAGICWAKE (example link)
ApplePushServiceTask (see below)
Most informative item emerged from the output of pmset -g assertions. For example ApplePushServiceTask in the following line:
pid 85(apsd): [0x0003b830000b90bd] 00:00:10 ApplePushServiceTask named: "com.apple.apsd-waitingformessages-push.apple.com"
The solution that seems to work in my particular case (not a general solution) was to disable :
/System/Library/LaunchDaemons/com.apple.apsd.plist using launchctl. But this cannot be done until you do a csrutil disable in the safe mode. I don't write instructions here because it need caution and you need to enable it later.
(to be updated)
This question is basically a duplicate of this one, except that the accepted answer on that question was, "it's not actually slower, you just weren't running the timing command correctly."
In my case, it actually is slower! :)
I'm on Windows 10. Here's the output from PowerShell's Measure-Command (the TotalMilliseconds line represents wall-clock time):
PS> Measure-Command {npm --version}
Days : 0
Hours : 0
Minutes : 0
Seconds : 1
Milliseconds : 481
Ticks : 14815261
TotalDays : 1.71472928240741E-05
TotalHours : 0.000411535027777778
TotalMinutes : 0.0246921016666667
TotalSeconds : 1.4815261
TotalMilliseconds : 1481.5261
A few other numbers, for comparison:
'{.\node_modules.bin\mocha}': 1300ms
'npm run test' (just runs mocha): 3300ms
npm help: 1900ms.
the node interpreter itself is ok: node -e 0: 180ms
It's not just npm that's slow... mocha reports that my tests only take 42ms, but as you can see above, it takes 1300ms for mocha to run those 42ms of tests!
I've had the same trouble. Do you have Symantec Endpoint Protection? Try disabling Application and Device Control in Change Settings > Client Management > General > Enable Application and Device Control.
(You could disable SEP altogether; for me the command is: "%ProgramFiles(x86)%\Symantec\Symantec Endpoint Protection\smc.exe" -stop.)
If you have some other anti-virus, there's likely a way to disable it as well. Note that closing the app in the Notification area might not stop the virus protection. The problem is likely with any kind of realtime protection that scans a process as it starts. Since node and git are frequently-invoked short-running processes, this delay is much more noticeable.
In Powershell, I like to measure the performance of git status, both before and after that change: Measure-Command { git status }
I ran into this problem long ago, I think it was an extension that I had. I use Visual Studio Code, and when it has no extensions and running bash:
//GIT Bash Configuration
"terminal.integrated.shell.windows": "C:\\Program Files\\Git\\bin\\bash.exe",
it actually flies, I use both OS, so I can tell the difference. Try using different tools and disabling some.
And if that still doesn't work, check your antivirus, maybe it's slowing down the process?
Been googling this all day, with no luck. Decided to uninstall Java to see what would happen and bingo, solved my problem. I know this is an old thread, but I found myself coming back to it so many times to see if I missed anything.
off topic:
Got to figure out how to get Java working now 🤦
Didn't know about Measure-Command, so I'll be using that in the future!
I had this problem. When I tried to run an application of my job in my home, I realized that in my job's laptop the app starts on 2 minutes but in my personal notebook it tooked 5 minutes or more.
After trying some possible solutions, finally I found the problem was that I installed Git Bash in my D drive partition which is a HDD. When I re-installed in C drive whichs is a SSD then the app started faster. However, I also moved Node.js to C drive to prevent another issues.
I'm building an arcade cabinet and would like to have random games launch after 15 minutes of inactivity. I'm not sure how to determine the time since the last user input. This is a pretty standard screensaver with xserver, however I can't seem to find a way to do it without x running.
Specifically I'm running RetroPie on a Raspberry Pi 2. X is installed but not running. The front end is emulationstation.
Any help would be appreciated, thanks.