I tried to build a project while it reports: # ./autogen.sh Can’t exec “aclocal”: No such file or directory at /usr/share/autoconf/Autom4te/FileUtils.pm line 326. autoreconf: failed to run aclocal: No such file or directory How should I handle this? How to install aclocal? yum install aclocal shows: No package aclocal available. Error: Unable to find a
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Tag: How to
How to add two static IPs for a Xen VM?
Posted onHello, I have installed Xen4Centos on Centos7, having single NIC card with bridge network and have two VMs on that. In one VM, I want to add two static IP one for webserver and one for mail server. So I have created IP alias in guest VM, it was created but it was not pinging
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Allowing root Access to NFS Directories
Posted onFor local filesystems, root usually has full access (read/write) to directories/files inside of it. But for NFS directory mounted from network, root usually has no permission to write to directories or files within the NFS directory. How to make root act similarly in an NFS directory to the behavior in local directories? The reason that
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How to install PARSEC correctly.
Posted onPARSEC is the most important CPU-bound benchmark for systems. It is huge and hard to install because it needs lots of 3-part libs. PARSEC download link for 3.0 version: http://parsec.cs.princeton.edu/download.htm#parsec I remembered I added the answer yesterday night but I could not see the answer currently. Anyway, let me add the answer again after I
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How to install NAS benchmark
Posted onNAS benchmark link: http://www.nas.nasa.gov/publications/npb.html For Ubuntu, remember to install gfortran (sudo apt-get install gfortran) and change config/make.def to install NAS benchmark. Other distros are similar.
How to install glibc, glibc-common and GD libraries independently?
Posted onI already have PHP and nginx installed and running on my on centOS 6.7. Please guide me, how can install glibc, glibc-common and GD libraries independently on my centOS 6.7 without crashing my system? I am not sure how you installed PHP and nginx. If they are installed from CentOS6.7’s Yum repository, you may install
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In Golang, how to convert a string to unicode rune array and back?
Posted onIn Golang, how to convert a string to unicode rune array and do the reverse way? Convert string s to a rune array: runes := []rune(s) Convert a rune array runes to string: str := string(runes)
In Golang, how to print string to STDERR?
Posted onIn Golang, the fmt.Println() is convenient to print to STDOUT. But how to print string to STDERR? In Go os package, “Stdin, Stdout, and Stderr are open Files pointing to the standard input, standard output, and standard error file descriptors.” So, you can use the WriteString function on File on os.Stderr to print string to
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Converting Error to String in Go Lang
Posted onIn Golang, fmt.Println(err) can print out the error err. But how to convert an error to a string explicitely? In Go, the error type is an interface type that has an interface type error interface { Error() string } An error variable represents any value that can describe itself as a string. Ref: https://golang.org/pkg/builtin/#error So,
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How to process a file line by line in Go?
Posted onIn the Go programming language, How to process a file line by line? An equivalent piece of Bash code could be while read line ; do echo $line done < ./input.txt You can make use of the bufio package’s Scan(). // open the file filepath f := os.Open(filepath) // create a scanner fs := bufio.NewScanner(f)
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How to convert the dmesg timestamps to easier to read format on Linux?
Posted onThe dmesg results from newer Linux kernels show the timestamps. It seems the time in seconds since the kernel start time. How to convert the dmesg timestamps to the real time on Linux? The dmesg timestamp is the time in seconds since the kernel starting time. Later dmesg has an -T option: -T, –ctime Print
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In Node.js, how to import functions from another JavaScript file?
Posted onIn Node.js, how to import functions from another JavaScript file like source common.sh in Bash? In the .js file to be imported such as ‘common.js’, organize functions to be exported like module.exports = { func1: function () { // func1 impl }, func2: function () { // func2 impl } }; In the other .js
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How to create a Reader from a string in Go?
Posted onIn Go, how to create a Reader from a string? Many APIs use a Reader as its input. In Go, the strings.NewReader(s) library function creates a Reader from a string. Check the doc at: https://golang.org/pkg/strings/#NewReader
How to grep a tab on Linux?
Posted onHow to grep a tab on Linux? Including ‘t’ seems not working. grep can grep tabs. The problem is likely the tab is not passed to grep. If you are using Bash, you can use ANSI-C quoting to pass the “tab” to grep: $ grep $’t’ file.txt Or, use Perl-style regex (only for GNU grep)
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How to get the full path and directory of a Makefile itself?
Posted onHow to get the full path and directory of a Makefile itself like finding Bash script’s own path? This 2 lines in Makefile get the full path and dir of the Makefile itself: mkfile_path := $(abspath $(lastword $(MAKEFILE_LIST))) mkfile_dir := $(dir $(mkfile_path)) The piece of code gets you Makefile, finds its absolute path and the
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how to use pc internet of window8 on iphone 4s via usb
Posted onhow to use pc internet on iPhone 4s wia usb cable, pc is of window 8 and in network setting its not showing of connection of I phones network I ever wrote a tutorial at http://www.systutorials.com/136003/iphone-connecting-internet-using-windows-pc-network-through-usb-cable/ . But please be aware that it worked only on specific OS combinations. So, I am not sure whether
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How to choose the key used by SSH for a specific host?
Posted onHow to choose a key used rather than the default ~/.ssh/id_rsa when ssh to a remote server for a specific host? You have at least 2 choices for choosing the key used by ssh. Taking ~/.ssh/key1 and user@example.com as the example here. Method one, specify the key in command line with the -i option of
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How to check whether a function has been defined in Bash?
Posted onI would like to know whether a function, say f1(), has already been defined in Bash. How should I do it? You can use the type -t to get a string of the type of the name: If the -t option is used, type prints a string which is one of alias, keyword, function, builtin,
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How to disable an option with a bash script?
Posted onIt is possible to set an option inside a Bash script such as set -o errexit. But how to do the reverse thing, that is, to unset an option? Change – to + to do the reverse thing of unseting an option in bash. For example, to unset the errexit option set by set -o
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How to get the metadata of an AWS S3 object?
Posted onI upload files using the aws cli http://www.systutorials.com/239665/uploading-large-files-amazon-s3-aws-cli/ . But how to get the metadata of an object in AWS S3? You can use the s3api‘s head-object command to get the metadata of an object. Taking one example: $ aws s3api head-object –bucket test-hkust –key dir2/fileupload/fb0c6353-a90c-4522-9355-7cd16cf756ff.file.txt It will print results like { “AcceptRanges”: “bytes”, “ContentType”:
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