Usually we use data[44:] to eliminate the header information of wav files, and then assume the rest data is PCM. This may not always be true. For the wav header of a PCMWAVEFORMAT, we can usually understand that a structure as follows is at the front, and then followed by Read more…
After my CentOS 7 upgrade, I rebooted it. It gets stuck and shows a prompt like this:
grub >
It is an annoying start.
Suppose we want to create a "lazy" data attributes ( "instance variables" in Smalltalk, or "data members" in C++) in a Python Class. We may required to use getattr to customize attribute access.
It is becoming pretty slow in SSH to a CentOS server.
Trying to print a verbose log:
$ ssh -vvvv my-host .... debug3: send packet: type 21 debug2: set_newkeys: mode 1 debug1: rekey out after 134217728 blocks debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug3: receive packet: type 21 debug1: SSH2_MSG_NEWKEYS received debug2: set_newkeys: mode 0 debug1: rekey in after 134217728 blocks debug1: Will attempt key: /Users/user/.ssh/id_rsa RSA SHA256:XXXXX/gNY explicit debug2: pubkey_prepare: done debug3: send packet: type 5 debug3: receive packet: type 7 debug1: SSH2_MSG_EXT_INFO received debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512> debug3: receive packet: type 6 debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug3: send packet: type 50 ..... <<<-- long long long silence here debug3: receive packet: type 51 <<<-- and then continue to access the server debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password debug3: start over, passed a different list publickey,gssapi-keyex,gssapi-with-mic,password debug3: preferred publickey,keyboard-interactive,password
首先下载 golang 的代码，可以从 https://golang.org/dl 或者中国的 mirror https://golang.google.cn/dl 下载最新的 go<version>.src.tar.gz. 然后开始编译就可以。
构建方法基本可以参考官方文档 就可以。
If we use Jetson Nano's default image to start our project, we may have some follow steps to make our work easier.
To speed up our dependencies updating for golang, or prepare some patterns for our special libraries, we probably consider to use a proxy to speed it up.
这几年这个博客都在使用 Google Analytics 服务。虽然每天被访问页面次数也就几百个，但我有时候也有点臭美的想知道是不是真的有用户在访问。最近偶然看了下 GA 的分析，发现来自台湾的用户特别高。
Bash script writing is a import approach to configure the linux system. Suppose we wish to add a user if not exists, the command may seems as follow:
TARGET_USER=alice
if (! id -u $TARGET_USER > /dev/null 2>&1 ); then
echo "creating user $TARGET_USER"
# adduser $TARGET_USER
fi
However, it is kind of too long. In this case short-circuiting is a alternative solution. (more…)