What’s the maximum number of mmap()‘ed ranges that a process can makes and how to set the limits on Linux? I have a program that mmap()s and mprotect()s lots ranges. After allocating many ranges, mprotect() starts to fail with ENOMEM error number. From the man page, ENOMEM means 2 possible problems: ENOMEM Internal kernel structures
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Tag: error
Git push error under CENTOS 6.7
Posted on$ git add file $ git commit -m “xxxx” $ git push error: The requested URL returned error: 403 Forbidden while accessing https://github.com fatal: HTTP request failed Change your ~/.gitconfig as follows: $ cat ~/.gitconfig [user] name = xxx email = xxx@gmail.com [remote “origin”] fetch = +refs/heads/*:refs/remotes/origin/* url= https://name@github.com/name/xxx.git
How to get file size in Python?
Posted onHow to get a file’s size in Python from the full path of a file? You can use this piece of Python code: os.path.getsize(file_path) It returns the size in bytes. It raises os.error if the file does not exist or is inaccessible. Manual of os.path.getsize(): https://docs.python.org/2/library/os.path.html#os.path.getsize
How to exit the program in Node.js?
Posted onWhen fatal error happened, we’d like to kill the program. How to exit the program in Node.js? You can use: process.exit() Here, “process” is a global process object. exit method ends the process. process.exit([code]) Ends the process with the specified code. If omitted, exit uses the ‘success’ code 0. To exit with a ‘failure’ code:
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git push error
Posted on$ git push error: The requested URL returned error: 403 Forbidden while accessing https://github.com/HarryWei/hummer.git/info/refs fatal: HTTP request failed Replace (or add) url=ssh://git@github.com/HarryWei/hummer.git with url=https://git@github.com/HarryWei/hummer.git under “[remote “origin”]” section in ~/.gitconfig file. Reference:http://stackoverflow.com/questions/7438313/pushing-to-git-returning-error-code-403-fatal-http-request-failed
What’s wrong with the messages like “UnrecovData 10B8B BadCRC” and “failed command: READ FPDMA QUEUED” on Linux?
Posted onI keep seeing messages in dmesg as follows with “exception Emask 0x10” -> “SError: { UnrecovData 10B8B BadCRC }” -> “failed command: READ FPDMA QUEUED” -> “hard resetting link”: [ 7395.936692] ata4.00: exception Emask 0x10 SAct 0xe000 SErr 0x280100 action 0x6 frozen [ 7395.936701] ata4.00: irq_stat 0x08000000, interface fatal error [ 7395.936703] ata4: SError: {
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mkfs refuses to make filesystem with message “is apparently in use by the system; will not make a filesystem here!”
Posted onI have a disk from another server installed on a new server. However, when I try to make a filesystem on it, mkfs reports # mkfs -t ext4 /dev/sdd1 mke2fs 1.42.8 (20-Jun-2013) /dev/sdd1 is apparently in use by the system; will not make a filesystem here! This is a new disk to the new server.
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How to make curl request pass the Squid proxy?
Posted onI use curl to send requests to remote servers like following command. curl http://example.com/send –date-urlencode “data=hello” However, it is blocked by the network proxy squid in some networks with message like (some info anonymized with “…”): ERROR The requested URL could not be retrieved POST /… HTTP/1.1 Proxy-Authorization: Basic … User-Agent: Mozilla/4.0 (compatible;) Host: …
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Printing “powernow-k8 transition frequency failed” after install XEN
Posted onAfter I installed XEN hypervisor, the tty0 (CTRL+ALT+F1) prints “powernow-k8 transition frequency failed” to STDOUT continously, how to solve it? sudo rmmod powernow_k8 From https://lists.debian.org/debian-user/2013/01/msg00754.html How to make the settings persistent (take effect after reboot)? 1, Create script file ‘/etc/init.d/stop_pwoerk8.sh’ as follows. harry2vera@node1:/etc/init.d$ cat stop_pwoerk8.sh #! /bin/sh rmmod powernow_k8 2, Add the full PATH of
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rtnetlink answers file exists
Posted onWhen you replace dynamic IP to static IP, you may need to restart your netwrok on Debian as follows. $sudo /etc/init.d/networking restart … …. reconfiguring network interfaces…rtnetlink answers file exists … However, error happens here “rtnetlink answers file exists”. How to solve it??? Run following commands could solve this problem # ip addr flush dev
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Required packages for building YouCompleteMe for Vim on Fedora 21
Posted onYouCompleteMe for Vim on Fedora 21 reports this error: [zma@laptop:~/.vim/bundle/YouCompleteMe]$ ./install.sh — The C compiler identification is GNU 4.9.2 — The CXX compiler identification is GNU 4.9.2 — Check for working C compiler: /usr/bin/cc — Check for working C compiler: /usr/bin/cc — works — Detecting C compiler ABI info — Detecting C compiler ABI info
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VirtualBox report “Kernel driver not installed” on Fedora 21
Posted onVitualBox is installed on Fedora 21 by # yum install VirtualBox The following packages are installed kmod-VirtualBox-3.18.7-200.fc21.x86_64-4.3.20-4.fc21.4.x86_64 VirtualBox-4.3.20-3.fc21.x86_64 There is the kernel modules package installed. However, when running virtualbox (after reboot), it reports: [zma@laptop:~]$ virtualbox WARNING: The vboxdrv kernel module is not loaded. Either there is no module available for the current kernel (3.18.7-200.fc21.x86_64) or
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How to make Chrome on iPhone (iOS) accept self assigned ssl keys fir websites?
Posted onThis tutorial introduces how to make Chrome accept self assigned ssl keys for websites: https://www.systutorials.com/50204/making-chrome-accept-self-signed-certificates-on-linux/ However, on iPhone, Chrome blocks me from access sites with self assigned keys. How to make Chrome on iPhone also accept the ssl keys? At the time when I wrote this reply, there is no way to add Certificate Authorities
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Get error message on usb2 stick – READ ONLY FILE SYSTEM. What should i do?
Posted onCant read or write to files on usb stick or move or copy them. Could you provide the dmesg output? It will help to understand your question. If it is formated on Windows, you may need to install the ntfs-3g package to write to the usb disk.
Fixing “Remote Host Identification Has Changed” Error When SSH to a Server
Posted onIf you encounter an error message like the one below when attempting to SSH to a server: @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that a host key has
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How to change number of replications of certain files in HDFS?
Posted onThe HDFS has a configuration in hdfs-site.xml to set the global replication number of blocks with the “dfs.replication” property. However, there are some “hot” files that are access by many nodes. How to increase the number of blocks for these certain files in HDFS? You can the replication number of certain file to 10: hdfs
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How to install no-ip update client on Linux Mint?
Posted onHow to install no-ip.com update client noip2 on Linux Mint 17? First, install the noip2 client: sudo su – cd /usr/local/src wget http://www.no-ip.com/client/linux/noip-duc-linux.tar.gz tar xzf noip-duc-linux.tar.gz cd no-ip-2.1.9-1 make make install Then, generate the configuration file noip2 -C Last, make noip2 daemon run at reboot crontab -e Add this line to crontab: @reboot /usr/local/bin/noip2 I’ve
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Setting sbt log level at the command line
Posted onsbt‘s log level can be set by execute set logLevel := Level.Error inside sbt. How to set the sbt log level at the command line? Add –error to sbt for specify the logLevel to error: sbt –error “your command”
How to resume a printing job on HP printer if the paper runs out on Linux?
Posted onHow to resume the printing job on HP printers if the paper runs out on Linux? A tip: “lifting the cover to access the toner and putting it down without touching anything else will clear the out of paper error and continue printing” from here.
Convention of error codes on Linux and Windows
Posted onWhat’s the error code conventions on Linux and Windows? Linux and Windows use 0 to indicate that the operation is successful and an integer that is larger than 0 for some errors. Linux System Error Codes On Linux, the system error codes is defined in 2 headers which you can find on your own box:
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