title: Linux

#+startup: content

Install

ISO installation

lsblk list all partiation mkfs format partiation fdisk manage partiation

lsblk
sudo umount....
format the partation: 
sudo mkfs -t ext4 /dev/sda1
sudo mkfs -t ext4 /dev/sda2
sudo mkfs -t ext4 /dev/sda
sudo dd if=.../ubuntu-20.04.3-desktop-amd64.iso of=/dev/sda bs=4M status=progress && sync
resize the host
....
sudo mkfs -t ext4 /dev/sda
sudo fdisk -l
sudo fdisk  /dev/sda -> m, g, n, 1, Enter, w

sudo dd if=/dev/nvm..p1 of=/dev/sda1
sudo dd if=/dev/nvm..p3 of=/dev/sda2


from windows: Rufus
Disk can delete all partation in linux 
lsblk -f
sudo mkfs -t ext4 /dev/sda
from Linux:
sudo dd if=~/Downloads/ubuntu-20.04.3-desktop-amd64.iso of=/dev/sda bs=4M status=progress && sync

backup system

one step to backup in USB

sudo dd if=/dev/nvmxx2 of=/dev/sda2 bs=4M status=progress && sync

old setting insert SSD usb $ lsblk

check the partition of whole disk

$ sudo fdisk -l

check the detail partation

$ sudo mkfs -t ext4 /dev/sda

format sda  disk (can also for partition )

$ sudo fdisk /dev/sda

make new partiation distribation for backup

$ sudo dd if=/dev/nvmxx2 of=/dev/sda2 bs=4M status=progress && sync

backup the whole system disk into sda2 backup partition

$ disk resize the restore partation

this step can open the Disks in APP, and resize the system disk,
better if the system disk is 10GB bigger than the backup partition.
Later for backup again, don't forget resize it back to backup again

$ sudo mkfs -t ext4 /dev/nvmxxx2

clean the system partition

$ sudo dd if=/dev/sda2 of=/dev/nvmxx2 bs=4M status=progress && sync

should be just fine

grub repair

for error : Minimal BASH-like line editing is supported......

grub > ls 
grub > ls (hd0,gptXX)/boot/grub

if XX partation returns many file, one is with grub.cfg, this is the one we want

grub > set root=(hd0,gptXX)
grub > set prefix=(hd0,gptXX)/boot/grub
grub > normal

enter the system

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install boot-repair
sudo grub-install /dev/where EFI partation is

Recover the fastplatte in windows

1. WIN+R diskpart
2. select disk (Disk)
3. clean
4. new add

write images in USB

  1. 下载ubuntu
  2. 下载USBwriter并安装
  3. 写入系

reboot

my computer : F12

Update nvidia drivers for linux

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt update 
ubuntu-drivers devices
sudo apt-get --reinstall install nvidia-430
    1.  will be asked for password
    2.  reboot
    3.  select Enroll MOK -> continue -> Yes -> Roboot
nvidia-sim
watch -n 1 nvidia-smi

chinese

export LC~CTYPE~=zh~CN~.UTF-8 sudo apt-get -y install language-pack-zh-hans 此应用压制中英文的同步变化, 尽量避免使用中文

Time Screensaver

NowSat Nov 5 12:29:50 2022, I just configured my computer for a time screensaver.

  • link

  • go the the link, for me only work with building from source, don't forget the dependence.

  • after install it add following into ~/.xscreensaver under section of programs:

    gluqlo -root \n\

  • install Xscreensaver if not with following, but before that, delete gnome-screensaver if exist.

    sudo apt-get install xscreensaver xscreensaver-data-extra xscreensaver-gl-extra

  • start Screensaver application, find the Gluqlo, and set it to be the only one, more setting is option

  • start startup application, add one as following, name and comment is as well(liberty)command is this: xscreensaver -nosplash

  • lauch keyshort, add keyshort as following, key combination is as personal wish

    xscreensaver-command -lock

  • change Wayland to xorg

    • sudo apt install xorg
    • sudo nano /etc/gdm3/custom.conf
    • WaylandEnable=false

  • now test the keyshort

System configuration collection

check port of application

ps -aux |grep mongo
netstat -nap |grep 80

open fire wall for port

sudo apt install firewalld add port : sudo firewall-cmd --add-port=80/tcp --permanent sudo firewall-cmd --remove-port=80/tcp --permanent restart firewall: sudo firewall-cmd --reload check port: sudo firewall-cmd --list-all

firewall

systemctl status firewalld systemctl stop firewalld systemctl disable firewalld systemctl enable firewalld

Shutdown Keyboard default

1. <span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8889em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">x</span><span class="mord mathnormal">in</span><span class="mord mathnormal">p</span><span class="mord mathnormal">u</span><span class="mord mathnormal" style="margin-right:0.01968em;">tl</span><span class="mord mathnormal">i</span><span class="mord mathnormal">s</span><span class="mord mathnormal" style="margin-right:0.13889em;">tF</span><span class="mord mathnormal">in</span><span class="mord mathnormal">d</span><span class="mord mathnormal">t</span><span class="mord mathnormal">h</span><span class="mord mathnormal">e</span><span class="mord mathnormal" style="margin-right:0.13889em;">T</span><span class="mord mathnormal">o</span><span class="mord mathnormal">u</span><span class="mord mathnormal">c</span><span class="mord mathnormal">h</span><span class="mord mathnormal">p</span><span class="mord mathnormal">a</span><span class="mord mathnormal">d</span><span class="mord mathnormal">an</span><span class="mord mathnormal">d</span><span class="mord mathnormal">i</span><span class="mord mathnormal">t</span><span class="mord mathnormal">s</span><span class="mord mathnormal" style="margin-right:0.10903em;">N</span><span class="mord mathnormal">A</span><span class="mord mathnormal" style="margin-right:0.05764em;">ME</span><span class="mord mathnormal">an</span><span class="mord mathnormal">d</span><span class="mord mathnormal" style="margin-right:0.07847em;">I</span><span class="mord mathnormal" style="margin-right:0.02778em;">D</span><span class="mord">2.</span></span></span></span> xinput set-prop 'NAME' 'Device Enabled' 0
   to close the Touchpad
3. but with following can be named as tpOn and tpOff in ./bashrc
alias tpOff="xinput set-prop 'SYNA1D31:00 06CB:CD48 Touchpad' 'Device Enabled' 0"
alias tpOn="xinput set-prop 'SYNA1D31:00 06CB:CD48 Touchpad' 'Device Enabled' 1"
4. Close Touchpad default in boost system
   the following in ~/.config/autostart/xinput.desktop

[Desktop Entry]
Type=Application
Exec=xinput set-prop 'SYNA1D31:00 06CB:CD48 Touchpad' 'Device Enabled' 0
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[zh_CN]=touchpad enable
Name=touchpad enable

autostart

Thunderbird

[Desktop Entry]
Type=Application
Exec=/usr/bin/thunderbird
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[en_US]=thunderbird
Name=thunderbird
Comment[en_US]=thunderbird
Comment=thunderbird

exchange Control Key and Caps Key

在/etc/default/keyboard文件中添加:

XKBOPTIONS="ctrl:nocaps

or

setxkbmap -option ctrl:nocaps

setting for 右键没反应 $ sudo add-apt-repository universe $ sudo apt install gnome-tweak-tool

right key no response

gsettings set org.gnome.desktop.peripherals.touchpad click-method areas

hotkey

C-M- t terminal C-M- p thunderbird C-M- e emacs C-M- f firefox C-M- j emacs windows switch C-M- t terminal C-M- w emacs worterbuch C-M- t terminal C-M- t terminal

Switch application Alt + Tab Switch window of an application Alt + Spc

Alt Ctrl Del 退出用户

in Einstellung, the executable command can be used in command for customized hotkey

clear caches

this command has been added to the .bashrc of the /root. only root user can call this command

alias freemem="sync; echo 3 > /proc/sys/vm/drop_caches && swapoff -a && swapon -a && printf '\n%s\n' 'Ram-cache and Swap Cleared' "

create customized dock to favorites

  • find the executable files and icon

  • create the desktop setting file: /usr/share/applications/myapp.desktop

  • change the settings and make it executable +x

  • new works as normal

    #!/usr/bin/env xdg-open
[Desktop Entry]
Version=1.0
Type=Application
Terminal=false
Exec=/path/to/yourapp
Name=YourApp
Comment=Description of YourApp
Icon=/path/to/yourapp.png

hstr

add-apt-repository ppa:ultradvorka/ppa
apt-get update
apt-get install hstr

the hh

commands

hits

  • assigne permition for delete
chmod -R u+rwx /usr/users/szhao/go-workspace/pkg/mod
  • /ect/ssh/sshd~config~
    • AllowedUsers cloud silin, allow such user login remotely

terminal

S-C-c : can copy out from terminal S-C-v : can paste into terminal C-h : backwards to delete C-j : enter C-k : cut after C-u : cut before

sammary

fdisk -l

fdisk /dev/nvme0n1p4 (m, p, n, ...)
mkfs.ext4 /dev/nvme0n1p4
sudo emacs /etc/fstab
/dev/nvme0n1p4 /home/silin/4GB ext4 defaults 0 0

in /etc/fstab, the command must be correct, otherwise the system can't booted.

cat < source1.c >> source2.c (add source1.c to the end of source2.c)

echo $PATH | tr \: \\n{=latex}

file management

在~内找filename的文件 find ~ -name filename

找到.bash~history内带有~"install"的内容 grep -n "install" .bash~history~

copy 110.txt to 111.txt echo | cat 110.txt > 111.txt

> 擦除再写 >> 追加写入

读取.sdsv~history的不重复内容~，再写入到.sdsv echo | sort -n .sdsv~history~ |uniq > .sdsv

directory operation

tree -L 2
alias open='nautilus'
open .

find uninstall and remove software

sudo apt list --installed | grep software
whereis software
sudo apt-get --purge remove software
sudo apt-get autoremove

su password config

sudo passwd :to configure the password of root user

get IP address

curl ifconfig.me

grep sort

grep -n "xxx" ./test.txt sort (--reverse -t " " -k 3 ) test.csv

softlink

ln -s filename linkname // 快捷方式
ln -s sourcefile softlinkname
filename加上绝对路径，linkname被移动后，仍能访问访问文件

hard link

ln filename linkname   //硬链接
不占用磁盘空间，重复连接到文件的inode点。
可以在不同地方通过硬连接对文件进行操作

cd to program with which

cd $(dirname $(which cling))

awk

delete the repeat : awk '!a[$0]++' file.txt

less

J down K up Space next page b previous page / search n next mark N previous mark q quit

静态库的制作

  1. 库方

    include/head.h lib/ src/ 将在src/中编写要实现的文件 并编译这些文件 $ gcc *.c -c -I ../include/ -I :链接头文件 再将这些编译后的打包 $ ar rcs libtest.a *.o ar : -archive 打包 检测 : nm libtest.a 前缀lib 和后缀.a 不能更改，实际名字是test

    最后将生成的libtest.a放到上级目录lib中， 可以将lib和include目录发送给甲方

  2. 甲方

    根据include/head.h 的头文件编写自己的应用文件main.c 编译main.c并链接头文件和库 $ gcc main.c -I ./include/ -L ./lib/ -ltest -o app -I : 连接头文件 -L : 链接库 -ltest : 链接库文件，去头lib 去尾.a -o: 指点生成的应用名

  3. 特点

    优点： 加载块，移植方便 缺点 ：部署更新麻烦，引用的重复文件重复储存，浪费空间

动态库的制作

编译 $ gcc *.c -c -fpic -I ../include -fpic 或者 fPIC : 特殊命令 打包 $ gcc -shared *.o -o libxxx.so 头lib 尾.so

使用和静态库相似， 根据头文件编写应用文件main.c $ gcc main.c -I ./inculde/ -L ./lib/ -lxxx -o app

对于linux生成的文件都是elf格式，并由ld-libc.so动态加载,需要让app能别找 到可以用环境变量或者配置文件

  1. 环境变量

    临时设置 $ export LD~LIBRARYPATH~=./lib 或者新增 $ export LD~LIBRARYPATH~=./lib:LD~LIBRARYPATH~

    临时设置可以使用相对路径，

    永久设置 用户 $ cat " LD~LIBRARYPATH~=./lib:LD~LIBRARYPATH~" >> ~/.bashrc $ source ~./bashrc

    永久设置 系统 $ sudo cat "LD~LIBRARYPATH~=./lib:LD~LIBRARYPATH~" >> /etc/profile $ source /etc/profile

  2. 修改配置文件

    配置文件/etc/ld.so.conf $ sudo cat "绝对路径/lib" >> /etc/ld.so.conf $ sudo ldconfig -v 激活配置

  3. 通过函数加载

    dlopen dlclose dlsym

sshpass login

ssh user@ip sshpass -p password ssh user@ip

Login without password

ssh-keygen -r rsa and drei mal enter ssh-copy-id cloud@ip ssh-copy-id localhost(warming:username should not be hostname)

ssh root login

emacs /etc/ssh/sshd~config~

  1. PermitRootLogin yes
  2. AllowUsers root OtherUser

output redirect

comands xxx >> output file comands xxx &>> str error file

recursive string replace

find . -type f -name "*.md" -exec sed -i 's/foo/bar/g' {} +
find . -type f -name "*.vue" -exec sed -i 's/store.state.Timer/store.state.Session01/g' {} +

Useful Software

tar

-x : extract -c: compose -v: show the process -z: with zip -f : such file

tar -zvcf xxx.tar.gz xxx
tar -zvxf xxx.tar.gz

fcitx for sougou

1. sudo apt install fcitx
download sougou
2. sudo apt  --fix-broken install(after download)
3. export LC_CTYPE=zh_CN.UTF-8 (for Emacs)

eog

eog xxx.png to view png with bluit in software eog

Okular

sudo apt-get install okular
F2 to constimizer
F7 mode view
C-gg to the page
C-n page down
C-p page up
M-n scroll down
M-p scroll up
C-b C-b add Annoation, 1 to note
SPC-b add bookmark
SPC-SPC rename bookmark
SPC-n bookmark down
SPC-p bookmark up

xournal

sudo apt install xournal

evince

evince xxx.pdf to view pdf file

stardict

download dictionaries from, http://download.huzheng.org/ and http://download.huzheng.org/zh_TW/ extract, and put them in usr/share/stardict/dic , if without this folder, create it with root

sudo apt install stardict
sudo apt install sdcv 
cd ~/Dropbox/cs/Tools
bzip2 -dk *.bz2
for i in *.tar.bz2; do sudo tar -xjvf "$i" -C /usr/share/stardict/dic ; done

kmplayer

sudo apt install kmplayer

simplescreenrecorder

sudo apt install simplescreenrecorder
alias ssr='simplescreenrecorder'
 ssr
Ctrl + Shift + Alt + V start or pause

Cvim

C-j moive to left 
C-k moive to right

hotopea

登陆photopea网站后，新建并上传图片 设置白色背景：图像 -> 调整 -> 色阶 点击下面的白色 后点击要处理的图片区域 去背景 ： 魔术棒 ， 点击去连续， 再直接delete

manual png create png

after edit a file.dot

dot -Tpng -O file.dot

gpg for secret

gpg --list-secret-keys
gpg -r user -e xxx.file
gpg -d xxx.file.gpg
after change xxx.file :gpg --verify xxx.file.gpg

ranger

apt install

pdftk

official web link

合并 pdftk 1.pdf 2.pdf 3.pdf output 123.pdf 多个不同页面合并 pdftk A=1.pdf B=2.pdf C=pdf cat A1-2 B2-3 C3 output abc.pdf 旋转第一页 pdftk in.pdf cat 1E 2-end output out.pdf 加密（128位） pdftk a.pdf output b.pdf owner~pw~ pass 加访问密码 pdftk a.pdf output b.pdf user~pw~ pass 解密 pdftk a.pdf input~pw~ pass output b.pdf 解压 pdftk a.pdf output b.pdf uncompress 压缩 pdftk a.pdf output b.pdf compress 修复 pdftk a.pdf output b.pdf 切割 pdftk a.pdf cat 1-end output b.pdf 分解成单页 pdftk a.pdf burst

Linux connect to Android

kedconnect on linux
kedconnect on android
with  the same internet connection can be found each other, and communication

The file can be found in Download folder of each devices

gs

remove active content from pdf

gs -dNOPAUSE -sDEVICE=pdfwrite -sOUTPUTFILE=CV.pdf -dBATCH CV.pdf

compress

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/prepress -dNOPAUSE -dQUIET -dBATCH -sOutputFile=compressed~PDFfile~.pdf input~PDFfile~.pdf

mpv player

sudo apt install mpv

mpv.conf

no-osd-bar # 去掉白色进度条
save-position-on-quit # 关闭时记住文件播放位置
no-border # 去掉边框

# 解码-字幕
vo=opengl:gamma-auto:icc-profile-auto
hwdec=auto
autofit-larger=92%
playcache=8192
lang=zh,chi
video-sync=display-resample

sub-codepage=enca:zh:utf8
sub-auto=fuzzy
sub-text-font-size=40
sub-text-shadow-offset=0
sub-text-color="#ffffffff"
sub-text-font="STZhongsong"
sub-codepage=utf8:gb18030

screenshot-template=mpv-screenshot-%f-%p
screenshot-format=png

osd-font="STZhongsong"
osd-font-size=36

--script=/Users/yourname/.config/mpv/autoload.lua

autoload.lua

-- This script automatically loads playlist entries before and after the
-- the currently played file. It does so by scanning the directory a file is
-- located in when starting playback. It sorts the directory entries
-- alphabetically, and adds entries before and after the current file to
-- the internal playlist. (It stops if the it would add an already existing
-- playlist entry at the same position - this makes it "stable".)
-- Add at most 5000 * 2 files when starting a file (before + after).
MAXENTRIES = 5000

function Set (t)
    local set = {}
    for _, v in pairs(t) do set[v] = true end
    return set
end

EXTENSIONS = Set {
    'mkv', 'avi', 'mp4', 'ogv', 'webm', 'rmvb', 'flv', 'wmv', 'mpeg', 'mpg', 'm4v', '3gp',
    'mp3', 'wav', 'ogv', 'flac', 'm4a', 'wma',
}

mputils = require 'mp.utils'

function add_files_at(index, files)
    index = index - 1
    local oldcount = mp.get_property_number("playlist-count", 1)
    for i = 1, #files do
        mp.commandv("loadfile", files[i], "append")
        mp.commandv("playlist-move", oldcount + i - 1, index + i - 1)
    end
end

function get_extension(path)
    match = string.match(path, "%.([^%.]+)" )
    if match == nil then
        return "nomatch"
    else
        return match
    end
end

table.filter = function(t, iter)
    for i = #t, 1, -1 do
        if not iter(t[i]) then
            table.remove(t, i)
        end
    end
end

function find_and_add_entries()
    local path = mp.get_property("path", "")
    local dir, filename = mputils.split_path(path)
    if #dir == 0 then
        return
    end
    local pl_count = mp.get_property_number("playlist-count", 1)
    if (pl_count > 1 and autoload == nil) or
       (pl_count == 1 and EXTENSIONS[string.lower(get_extension(filename))] == nil) then
        return
    else
        autoload = true
    end

    local files = mputils.readdir(dir, "files")
    if files == nil then
        return
    end
    table.filter(files, function (v, k)
        local ext = get_extension(v)
        if ext == nil then
            return false
        end
        return EXTENSIONS[string.lower(ext)]
    end)
    table.sort(files, function (a, b)
        local len = string.len(a) - string.len(b)
        if len ~= 0 then -- case for ordering filename ending with such as X.Y.Z
            local ext = string.len(get_extension(a)) + 1
            return string.sub(a, 1, -ext) < string.sub(b, 1, -ext)
        end
        return string.lower(a) < string.lower(b)
    end)

    if dir == "." then
        dir = ""
    end

    local pl = mp.get_property_native("playlist", {})
    local pl_current = mp.get_property_number("playlist-pos", 0) + 1
    -- Find the current pl entry (dir+"/"+filename) in the sorted dir list
    local current
    for i = 1, #files do
        if files[i] == filename then
            current = i
            break
        end
    end
    if current == nil then
        return
    end

    local append = {[-1] = {}, [1] = {}}
    for direction = -1, 1, 2 do -- 2 iterations, with direction = -1 and +1
        for i = 1, MAXENTRIES do
            local file = files[current + i * direction]
            local pl_e = pl[pl_current + i * direction]
            if file == nil or file[1] == "." then
                break
            end

            local filepath = dir .. file
            if pl_e then
                -- If there's a playlist entry, and it's the same file, stop.
                if pl_e.filename == filepath then
                    break
                end
            end

            if direction == -1 then
                if pl_current == 1 then -- never add additional entries in the middle
                    mp.msg.info("Prepending " .. file)
                    table.insert(append[-1], 1, filepath)
                end
            else
                mp.msg.info("Adding " .. file)
                table.insert(append[1], filepath)
            end
        end
    end

    add_files_at(pl_current + 1, append[1])
    add_files_at(pl_current, append[-1])
end

mp.register_event("start-file", find_and_add_entries)

mellplayer

sudo apt-get install libmpv-dev mpv

thunderbird

Alt to open the menubar,
Ansicht Anpassen to setting ungelesen

For Filter:
cd ~/.thunderbird/4r373mm9.default-release/ImapMail/imap.gmail.com
import msgFilterRules.dat to Gmail

EverSync

Eversync sync all bookmarks between chrome and firefox with G Konten

IPFS

download go-ipfs and untar
cp ipfs /usr/local/bin and sudo ./install.sh

sudo apt install ipfs

ipfs init
export EDITOR=/usr/bin/emacs
ipfs config edit
ipfs id
ipfs  help


mkdir IPFS
echo "balabalu" > hallo.org
ipfs add hallo.org  :get file_hash
ipfs cat file_hash
ipfs.io/ipfs/file_hash

push

ipfs add -r . (we get all file_hash(s), and a folder_hash(IPFS))
ipfs name publish folder_hash  (: to IDHASH)

in Webborser: ipfs.io/ipns/IDHASH


ipfs name resolve IDHASH : to HASH_file

特殊加密，暂时不用
ipfs key gen --type=rsa --size=2048 IPFS
ipfs name publish --key=IPFS folder_hash

ipfs config --json API.HTTPHeaders.Access-Control-Allow-Methods '["PUT", "GET", "POST","OPTIONS"]'

ipfs config --json API.HTTPHeaders.Access-Control-Allow-Origin '["*"]'

ipfs config --json API.HTTPHeaders.Access-Control-Allow-Credentials '["true"]'

ipfs config --json API.HTTPHeaders.Access-Control-Allow-Headers '["Authorization"]'

ipfs config --json API.HTTPHeaders.Access-Control-Expose-Headers '["Location"]'


http://localhost:5001/webui


ipfs files mkdir /Docu

ipfs files ls /Docu

ipfs file cp /ipfs/HASH

GPG

terminal encrypt gpg --recipient ID --output en.org --encrypt source.org terminal decrypt gpg en.org emacs encrypt epa-encrypt-file emacs decrypt epa-decrypt-file

encrypt by terminal, once decrypt by emacs, just as normal file, can be edited anytime encrypt by emacs with password, passwd will be ask every time by after edit if epa-file-select-key is t

Zulip Rocket Chat

System control

system backup

mount rsync

查看系统的磁盘 :lsblk 再将磁盘(也可以是某个分区)挂载到某个点 :

该磁盘可以是正在使用的磁盘或者分区

 mount /dev/disk /media/Linux
sudo mount /dev/sda1 /media/Backup

rsync -aAXv --delete --exclude=media target backup/LinuxBackUp20200316
my opera 

rsync -aAXv /home/sx/ /media/sx/A672BA1B72B9EFE3/linuxbackup/home/

如果要恢复，重复上面的过程，再将target backup 交换

system performance

  1. systemlastanzeigen sudo apt install indicator-multiload

  2. dependence

sudo apt-get install gir1.2-gtop-2.0 gir1.2-networkmanager-1.0 gir1.2-clutter-1.0

  1. Ubuntu Software

search for : system moniter extension

  1. install and configure performance

hostname

hostnamectl hostnamectl set-hostname cat /etc/hostname cat /etc/hosts

chinese config

emacs chinese input

sudo apt install fcitx download sougou for linux sudo dpkg -i sougou...... fcitx set global restart configuration to add sougou chinese

$ local -a |grep zh sudo apt-get -y install language-pack-zh-hans $ local -a |grep zh to see zh is installed

export LC~CTYPE~=zh~CN~.UTF-8 to language configuration and auto install drivers to zh~CN~.UTF-8 so in emacs can input sougou, here we go

chinese output pdf

for a orgmode file with 汉字 pandoc xxxx.org -o xxxx.pdf pandoc xxxx.org -o xxxx.pdf --pdf-engine=xelatex 如果没有汉字支持

fc-list -f "%{family}\n"  :lang=zh
pandoc test.org -o test.pdf --pdf-engine=xelatex -V mainfont="AR PL KaitiM GB"

找到支持的格式，再指明

sed

a add new line(s) after match with context behind a c replace the current line in match with context behind c i add context behind i before match s repace d delete

sed -rn '/2\/1/s/00/**/pg' test2.csv

  • sed:
  • -rn : no default output and allow \
  • ' ' : aufrufen
  • /2\/1: reg pattern
  • s: search
  • 00: all 00

-**: will be replaced by**

  • p: print
  • g: global replace
  • test2.csv: input file

sed 's/ //pg' test2.csv

Makefile

gcc 调用 make 来构造

格式

目标 ： 依赖 Tab 命令

1example

实列文件：add.c head.h main.c maul.c sub.c 直接在terminal 用gcc ：$ gcc add.c main.c sub.c -o app

Makefile : $ touch Makefile

app: main.c add.c sub.c mul.c
    gcc main.c add.c sub.c mul.c

$ make

2修改后只编译改动后的文件

Makefile : $ touch Makefile

app: main.o add.o sub.o mul.o
    gcc main.o add.o sub.o mul.o -o app

main.o: main.c
    gcc -c main.c -o main.o

add.o: add.c
    gcc -c add.c -o add.o

sub.o: sub.c
    gcc -c sub.c -o sub.o

mul.o: mul.c
    gcc -c mul.c -o mul.o

$ make 所有源文件的修改过，即时间戳晚于生成的目标文件，则重新编译

3使用自动变量

$@ :目标 $< :第一个依赖 $^ :所有依赖 Makefile : $ touch Makefile

obj =   main.o add.o sub.o mul.o
target = app

$(target):$(obj)
    gcc $(obj) -o $(target)  // gcc $^ -o $@

%.o:%.c
    gcc -c $< -o $@

$ make

4增加可移植性

wildcard :查找指定目录下的指定类型文件 src = $(wildcard ./*.c) 将当前目录下所有的.c 找到，并赋给src

patsubst :匹配替换 obj = $(patsubst %.c, %.o, $(src)) 将src中的所有.c替换为.o

Makefile : $ touch Makefile

src = $(wildcard ./*.c)
obj = $(patsubst %.c, %.o $(src))
target = app

$(target):$(obj)
    gcc $^ -o $@

%.o:%.c
    gcc -c $< -o $@

$ make 此文件在别的目录下也能使用

5清洁中间的生成的不必要保存文件

make 一般直接执行终结目标，但是可以直接指定make的函数 clean : 删除不必要的文件，-f : 强制删除，不管有没有该文件，- : 前置-后，遇到错误执行，直接跳过

src = $(wildcard ./*.c)
obj = $(patsubst %.c, %.o $(src))
target = app

$(target):$(obj)
    gcc $^ -o $@

%.o:%.c
    gcc -c $< -o $@

clean:
    rm $(obj) $(target)
    rm $(obj) $(target) -f
    -rm $(obj) $(target) -f

$ make $ make clean

BetreibenSystem

Program execution level

Multi Process : Parallel single Process has more thread : Concurrency single thread can work in Synchronous or Asynchronous

Multi Process

queue communication

  1. one way communication server to client

    Server.c

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"
#include "string.h"

#define messagelen 124


struct messqueue
{
  long type;
  char message[messagelen];
  char ID[4];
};


int main(int argc, char *argv[])
{
  int msgid;
  int key;
  int receivelen;
  int conut = 0;
  struct messqueue sendbuffer;
  sendbuffer.type = 100;

  key = ftok("./a.c", 'a');
  if (key < 0) {
    printf("create key for server failed \n");
    return -1;
  }

  //create the massage queue
  msgid= msgget(key, IPC_CREAT | 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }
  printf("create massage queue success  with msgid %d.\n",  msgid);


  do {
    memset(sendbuffer.message, 0, messagelen);
    //input your massage
    printf("please input your massage you want to send to massage queue \n");
    scanf("%s", sendbuffer.message);

    //wirte the massage(which is now in your struct messqueue) into massage queue msgid
    msgsnd(msgid, (void *)&sendbuffer, strlen(sendbuffer.message), 0);
    conut++;
  }while (conut < 3);

  msgctl(msgid, IPC_RMID, NULL);

  system("ipcs -q");
  return 0;
}

    Client.C

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"
#include "string.h"

#define messagelen 124


struct messqueue
{
  long type;
  char message[messagelen];
  char ID[4];
};


int main(int argc, char *argv[])
{
  int msgid;
  int key;
  int receivelen;
  int conut = 0;
  struct messqueue sendbuffer;
  sendbuffer.type = 100;

  key = ftok("./a.c", 'a');
  if (key < 0) {
    printf("create key for server failed \n");
    return -1;
  }

  //create the massage queue
  msgid= msgget(key, IPC_CREAT | 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }
  printf("create massage queue success  with msgid %d.\n",  msgid);


  do {
    memset(sendbuffer.message, 0, messagelen);
    //input your massage
    printf("please input your massage you want to send to massage queue \n");
    scanf("%s", sendbuffer.message);

    //wirte the massage(which is now in your struct messqueue) into massage queue msgid
    msgsnd(msgid, (void *)&sendbuffer, strlen(sendbuffer.message), 0);
    conut++;
  }while (conut < 3);

  msgctl(msgid, IPC_RMID, NULL);

  system("ipcs -q");
  return 0;
}

  2. two ways communication server vs client

    Server.c

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"
#include "string.h"

#define messagelen 124


struct messqueue
{
  long type;
  char message[messagelen];
  char ID[4];
};


int main(int argc, char *argv[])
{
  int msgid;
  int key;
  int receivelen;
  int conut = 0;
  pid_t pid;
  struct messqueue sendbuffer, receiverbuffer;


  key = ftok("./b.c", 'a');
  if (key < 0) {
    printf("create key for server failed \n");
    return -1;
  }

  //create the massage queue
  msgid= msgget(key, IPC_CREAT | 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }
  printf("create massage queue success  with msgid %d.\n",  msgid);

  pid = fork();

  if (pid > 0) {   //server father process write tpye 100
    sendbuffer.type = 100;

    while(1) {
      memset(sendbuffer.message, 0, messagelen);
      //input your massage
      printf("please input your massage you want to send to massage queue \n");
      scanf("%s", sendbuffer.message);

      //wirte the massage(which is now in your struct messqueue) into massage queue msgid
      msgsnd(msgid, (void *)&sendbuffer, strlen(sendbuffer.message), 0);
      conut++;
    }
  }

  if (pid == 0) {    //server child process read tpye 200
    while (1) {
      memset(receiverbuffer.message, 0, messagelen);
      msgrcv(msgid, (void *)&receiverbuffer, messagelen, 200, 0);
      printf("the receive massage of massage queue in server is %s \n", receiverbuffer.message);
    }

  }

  msgctl(msgid, IPC_RMID, NULL);

  system("ipcs -q");
  return 0;
}

    Client.c

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"
#include "string.h"

#define messagelen 124


struct messqueue
{
  long type;
  char message[messagelen];
  char ID[4];
};


int main(int argc, char *argv[])
{
  int msgid;
  int key;
  int receivelen;
  int conut = 0;
  pid_t pid;
  struct messqueue sendbuffer, receiverbuffer;


  key = ftok("./b.c", 'a');
  if (key < 0) {
    printf("create key for server failed \n");
    return -1;
  }

  //create the massage queue
  msgid= msgget(key, IPC_CREAT | 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }
  printf("create massage queue success  with msgid %d.\n",  msgid);

  pid = fork();

  if (pid == 0) { // client child process for write tpye 200
    sendbuffer.type = 200;

    while(1) {
      memset(sendbuffer.message, 0, messagelen);
      //input your massage
      printf("please input your massage you want to send to massage queue \n");
      scanf("%s", sendbuffer.message);

      //wirte the massage(which is now in your struct messqueue) into massage queue msgid
      msgsnd(msgid, (void *)&sendbuffer, strlen(sendbuffer.message), 0);
      conut++;
    }
  }

  if (pid > 0) {  // client child process read type 100
    while(1){
      memset(receiverbuffer.message, 0, messagelen);
      msgrcv(msgid, (void *)&receiverbuffer, messagelen, 100, 0);
      printf("the receive massage of massage queue in server is %s \n", receiverbuffer.message);
    }
  }

  msgctl(msgid, IPC_RMID, NULL);

  system("ipcs -q");
  return 0;
}

pipe communication

  1. named

    1. In current directory: mkfifo("./myfifo", 0777);

    with mkfifo creat a file, so that other unrelated process can commu

    1. In one process : fd = open("./myfifo", O~WRONGLY~);

    open the file, and : write(fd, &process~inter~,1); change the pipe variable.

    1. In other process : fd = open("./myfifo",O~RDONLY~);

    open the file, and : while(process~inter~ == 0); can be controled by pipe variable

  2. unnamed

    1. In one process diff threads creat place for pipe : int fd[2]; one for main thread, one for new thread creat pipe : int ret = pipe(fd);

      in new thread : read(fd[0], &process~inter~ 1); if nothing to read, sleep in main thread do its stuff, after finish : write(fd[1], &process~inter~, 1); let new pthread run

      remeber: wirte at frist in fd[1], and then read at fd[0]

signal communication

  1. alarm

    alarm(10); wait for 10 seconds and kill itself send signal as 14 to itself

  2. kill

    kill(pid, 9); send signal 9 to pid process

  3. raise

    raise(9); == kill(getpid(), 9);

  4. pause

    pause(); stoped for ever

  5. signal

    signal(signal~ID~, self~function~); self function or SIG~ING~ or SIG~DFL~

  6. exit

    exit(0) will also send signal 17 (SIGCHID) to its father thread;

semaphore communication

  1. key

    key can be 2 differ

    1. For father and son process : IPC~PRIVATE~ :
    2. For unrelated process : self~def~ key
    
int key;
key = ftok("./a.c", 'a');
if (key < 0) {
  printf("create key for server failed \n");
  return -1;
}
printf("create key for server success \n");

  2. memcpy

    memcpy(p, "niao",4);

  3. shmget

    shmid = shmget(IPC~PRIVATE~, 128, 0777); shmid = shmget(key, 128, IPC~CREAT~ | 0777);

  4. shmat

    char *p = (char *) shmat(shmid, NULL, 0); after mapping to p : can be manipulated scanf("%s", p); printf("%s", p);

  5. shmdt

    delete the mapping of p to shared memory shmdt(p); after that, the manipulation of p is not allowed, and well be segmention fault

  6. shmctl

    delete the created shared memory shmctl(shmid, IPC~RMID~, NULL); == iprcm -m shmid

  7. IPC manipulation

    show : ipcs -m(shared memory) -q(message queue) -s(semaphores) delete : ipcrm -m shmid /-q msgid /-s semid

  8. msgget

    msgid= msgget(IPC~PRIVATE~, 0777);

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"

int main(int argc, char *argv[])
{
  int msgid;

  msgid= msgget(IPC_PRIVATE, 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }

  printf("create massage queue success  with msgid %d.\n",  msgid);

  system("ipcs -q");
  return 0;
}


    
------ Nachrichtenwarteschlangen --------
Schlüssel msqid      Besitzer   Rechte     Benutzt-Bytes Nachrichten 
0x61091797 2          silin      777        0            0           
0x00000000 4          silin      777        0            0           
0x00000000 5          silin      777        0            0           
0x00000000 6          silin      777        0            0           
0x00000000 7          silin      777        0            0           
0x00000000 8          silin      777        0            0           
0x00000000 9          silin      777        0            0           
0x00000000 10         silin      777        0            0           
0x00000000 11         silin      777        0            0           
0x00000000 12         silin      777        0            0           

create massage queue success  with msgid 12.

  9. msgctl

    msgctl(msgid, IPC~RMID~, NULL); == ipcrm -q msgid

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"

int main(int argc, char *argv[])
{
  int msgid;

  msgid= msgget(IPC_PRIVATE, 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }

  printf("create massage queue success  with msgid %d.\n",  msgid);

  system("ipcs -q");
  return 0;
}

  10. msgsnd & msgrcv

    msgsnd(msgid, (void *)&sendbuffer, strlen(sendbuffer.message), 0);

    receivelen = msgrcv(msgid, (void *)&receiverbuffer, messagelen, 100, 0);

    #include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"
#include "string.h"

#define messagelen 124


struct messqueue
{
  long type;
  char message[messagelen];
  char ID[4];
};


int main(int argc, char *argv[])
{
  int msgid;
  int receivelen;
  struct messqueue sendbuffer, receiverbuffer;
  sendbuffer.type = 100;
  receiverbuffer.type = 100;

  //create the massage queue
  msgid= msgget(IPC_PRIVATE, 0777);
  if (msgid < 0) {
    printf("creat massage queue failed .\n");
    return -1;
  }
  printf("create massage queue success  with msgid %d.\n",  msgid);

  //input your massage
  printf("please input your massage you want to send to massage queue \n");
  scanf("%s", sendbuffer.message);

  //wirte the massage(which is now in your struct messqueue) into massage queue msgid
  msgsnd(msgid, (void *)&sendbuffer, strlen(sendbuffer.message), 0);

  //clear receiverbuffer.massage
  memset(receiverbuffer.message, 0, messagelen);
  //read massage to receiverbuffer from massage queue msgid
  receivelen = msgrcv(msgid, (void *)&receiverbuffer, messagelen, 100, 0);

  printf("the receiverbuffer massage have %s .\n", receiverbuffer.message);
  printf("the long is %d .\n", receivelen);


  msgctl(msgid, IPC_RMID, NULL);

  system("ipcs -q");
  return 0;
}


    
------ Nachrichtenwarteschlangen --------
Schlüssel msqid      Besitzer   Rechte     Benutzt-Bytes Nachrichten 
0x61091797 2          silin      777        0            0           
0x00000000 4          silin      777        0            0           
0x00000000 5          silin      777        0            0           
0x00000000 6          silin      777        0            0           
0x00000000 7          silin      777        0            0           
0x00000000 8          silin      777        0            0           
0x00000000 9          silin      777        0            0           
0x00000000 10         silin      777        0            0           
0x00000000 11         silin      777        0            0           
0x00000000 12         silin      777        0            0           

create massage queue success  with msgid 14.
please input your massage you want to send to massage queue 
the receiverbuffer massage have
the long is 6 .

  11. semget

    semid = semget(IPC~PRIVATE~,3 , 0777);

  12. semctl

    semctl(semid, 0, IPC~RMID~, NULL);

Multi Thread

1 pthread~create~.c

using pthread~create~ create new thread(thread~fun~) with arguements("new thread"). In new thread call function print~id~ with giving arguements.

This programm can't compiled in Babel, please save this as a .c file, and compile with -pthread

#include "apue.h"

void print_id(char *s)
{
  pid_t pid;
  pthread_t tid;

  pid = getpid();
  tid = pthread_self();

  printf("%s pid is %u, and tid is 0x%x\n", s, pid, (int) tid);
}

void *thread_fun(void *arg)
{
  printf("In son thread, can't get the father tid \n");

  print_id(arg);
  return (void *)0;
}

int main( )
{
  pthread_t ntid;
  int err;
  err = pthread_create(&ntid, NULL, thread_fun, "new thread");

  if (err != 0) {
    printf("create new thread is failed\n");
    return 0;
  }
  printf("In father thread, the new THREAS is 0x%x \n", (int)ntid );

  print_id("main thread");
  sleep(2);

  return 0;
}

2 pthread~id~.c

using pid = getpid() to get pid of current pthread

#include <stdio.h>
#include "unistd.h"
#include "sys/types.h"
#include "stdlib.h"
#include "signal.h"
#include "sys/msg.h"
#include "string.h"

int main( )
{
  pid_t pid;
  pthread_t tid;

  pid = getpid();
  tid = pthread_self();

  printf("pid is %d , and tid is %x\n", pid, (int)tid );
  return 0;
}



pid is 3406 , and tid is 960c4c0

3 pthread~jion~.c

pthread~jion~(tid, &reval) 可以回收主线程发起的副线程tid，并由 副线程指定返回值给reval.但是副线程如自己调用了 pthread~detach~(pthread-self()) 可以阻止主线程的jion

#include "apue.h"

void *thread_fun1(void *arg){
  printf("New thread out with return\n");
  return (void *)1;
}

void *thread_fun2(void *arg){
  printf("New thread out with pthread_exit\n");
  pthread_detach(pthread_self()); // detach it self
  pthread_exit((void *)2);
}


int main( )
{
  pthread_t tid1, tid2;
  int err1, err2;
  void  *reval1, *reval2;

  err1 = pthread_create(&tid1, NULL, thread_fun1, NULL); 
  err2 = pthread_create(&tid2, NULL, thread_fun2, NULL); 

  if (err1 || err2) {
    printf("The create of new thread is failed\n");
  }

  printf("the thread 1 has return as %d\n", pthread_join(tid1, &reval1) );
  printf("the thread 2 has return as %d\n", pthread_join(tid2, &reval2) );

  printf("the thread 1 has return code %d\n",(int*)reval1 );
  printf("the thread 2 has return code %d\n",(int*)reval2 );

  return 0;
}

4 pthread~cancel~.c

从主线程来的pthread~cancel~(tid)作用到tid的副线程时， 如果副线程设置为pthread~setcancelstate~(PTHREAD~CANCELDISABLE~, NULL) 则取消请求被忽视

如果副线程设置为pthread~setcancelstate~(PTHREAD~CANCELENABLE~, NULL); 则取消请求在下一个取消点被执行

如果副线程设置为pthread~setcanceltype~(PTHREAD~CANCELASYNCHRONOUS~, NULL); 则取消请求被立即执行

#include "apue.h"

void *thread_fun(void * arg){
  int stateval;
  int typeval;

  //  set cancel to be disable
  stateval = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
  if (stateval != 0) {
    printf("set cancel state to disable is failed\n");
  }
  printf("I'm New thread here !\n");
  sleep(4);


  //set cancel to be enable, will be canceled at the first cancel point
  stateval = pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
  if (stateval != 0)
    printf("set cancel state to enable is failed\n");
  else
    printf("about to set cancel enable\n");   // print is a cancel point

  //set cancel to be enable and immediately
  typeval = pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
  if (typeval != 0) {
    printf("set cancel state to immediately failed\n");
  }

  //cancel points
  printf("first place to cancel:\n");
  printf("second place to cancel:\n");
  return (void *)20;
}



int main( )
{
  pthread_t tid;
  int err, cval, jval;
  void * rval;

  err = pthread_create(&tid, NULL, thread_fun, NULL);
  if (err != 0) {
    printf("creat new thread is failed\n");
    return 0;
  }
  sleep(2);

  cval = pthread_cancel(tid);
  if (cval != 0) {
    printf("cancel the new thread is failed\n");
    return 0;
  }

  jval = pthread_join(tid, &rval);
  if (jval != 0) {
    printf("join thread  is failed\n");
    return 0;
  }
  printf("new thread has return code of %d\n", (int) rval );

  return 0;
}

5 pthread~rwlock~.c

pthread~rwlockt~ rwlock; 声明 pthread~rwlockinit~(&rwlock); 初始化 pthread~rwlockwrlock~(&rwlock); 写锁 pthread~rwlockrdlock~(&rwlock); 读锁 pthread~rwlockunlock~(&rwlock); 解锁 pthread~rwlockdestroy~(&rwlock); 销锁

#include "apue.h"
int num;
pthread_rwlock_t rwlock;

void * thread_fun1(void *arg){
  int err;
  sleep(1);
  pthread_rwlock_wrlock(&rwlock);  // write mode lock
  // pthread_rwlock_rdlock(&rwlock);   // read mode lock

  printf("thread 1 print num as %d\n",num );
  sleep(5);
  printf("thread 1 is over \n");

  pthread_rwlock_unlock(&rwlock);
  return (void *)0;
}

void * thread_fun2(void *arg){
  int err;
  pthread_rwlock_wrlock(&rwlock);
  //  pthread_rwlock_rdlock(&rwlock);

  printf("thread 2 print num as %d\n",num );
  sleep(5);
  printf("thread 2 is over \n");

  pthread_rwlock_unlock(&rwlock);
  return (void *)0;
}

int main( )
{
  pthread_t tid1, tid2;
  int err;

  err = pthread_rwlock_init(&rwlock, NULL);
  if (err) {
    printf("init failed\n");
    return 0;
  }

  err = pthread_create(&tid1, NULL ,thread_fun1, NULL);
  if (err) {
    printf("create of the first thread fail\n");
    return 0;
  }

  err = pthread_create(&tid2, NULL ,thread_fun2, NULL);
  if (err) {
    printf("create of the second thread failed\n");
    return 0;
  }

  pthread_join(tid1, NULL);
  pthread_join(tid2, NULL);

  pthread_rwlock_destroy(&rwlock);

  return 0;
}

6 pthread~attr~.c

seeing pthread~attr~.c pthread~attrinit~(&attr) using : pthread~attrsetdetachstate~(&attr, PTHREAD~CREATEDETACHED~); OR: pthread~attrsetdetachstate~(&attr, PTHREAD~CREATEJOINABLE~); 决定该线程是否可以被jion.

#include "apue.h"

void *thread_fun1(void *arg)
{
  printf("I am new thread  1\n");
  return (void *)1;
}


void *thread_fun2(void *arg)
{
  printf("I am new thread  2 \n");
  return (void *)2;
}

int main(int argc, char *argv[])
{
  pthread_t tid1, tid2;
  int err;

  //def attr and init and set to be spreate
  pthread_attr_t attr;
  pthread_attr_init(&attr);
  //  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);  

  err = pthread_create(&tid1, &attr, thread_fun1, NULL);
  if (err) {
    printf("create new thread 1 failed \n");
    return 0;
  }

  err = pthread_create(&tid2, NULL, thread_fun2, NULL);
  if (err) {
    printf("create new thread 2 failed \n");
    return 0;
  }

  err = pthread_join(tid1, NULL);
  if (!err) 
    printf("join thread 1 success \n");
  else 
    printf("jion thread 1 failed \n");


  err = pthread_join(tid2, NULL);
  if (!err) 
    printf("join thread 2 success \n");
  else 
    printf("jion thread 2 failed \n");

  pthread_attr_destroy(&attr);

  return 0;
}

7 pthread~mutex~.c

pthread~mutexlock~(&mutex) 和 pthread~mutexunlock~(&mutex) 可以锁住之间的的任何变量， 所以不同线程之间的访问和赋值只能错开时间， 这样就不会造成线程之间变量值不受控制的错误

#include "apue.h"

struct student{
  int age;
  int size;
} stu;

int i;
pthread_mutex_t mutex;

void *thread_fun1(void *arg){
  while(1){
    //    pthread_mutex_lock(&mutex);
    stu.age = i;
    stu.size = i;
    i++;
    if (stu.age != stu.size) {
      printf("thread 1 %d, %d,\n", stu.age, stu.size);
      break;
    }
    //    pthread_mutex_unlock(&mutex);
  }
  return (void *)0;
}


void *thread_fun2(void *arg){
  while (1) {
    //    pthread_mutex_lock(&mutex);
    stu.age = i;
    stu.size = i;
    i++;
    if (stu.age != stu.size) {
      printf("thread 2 %d, %d,\n", stu.age, stu.size);
    }
    //    pthread_mutex_unlock(&mutex);
  }
  return(void *)0;
}

int main( )
{
  pthread_t tid1, tid2;
  int err1, err2;

  err1 = pthread_create(&tid1, NULL, thread_fun1, NULL);
  err2 = pthread_create(&tid2, NULL, thread_fun2, NULL);  
  if (err1 || err2) {
    printf("the create o pthread 1 and pthread 2 failed\n");
  }

  pthread_join(tid1, NULL);
  pthread_join(tid2, NULL);

  return 0;
}

8 pthread~interpetercontroll~.c

用主线程给一个可交换变量赋值，来控制副进程的执行， only if in main thread, parameter interpeter be assigned to 1, in side thread can start to run.

#include <stdio.h>
#include "stdlib.h"
#include <unistd.h>
#include "pthread.h"

int interpeter = 0;

void *mythread(void *num){
  while(interpeter == 0);
  int i = 0;
  for (i = 0; i < 10; ++i) {
    printf("In my thread there is %d\n", i);
    usleep(100);
  }
  return (void *)0;
}

int main(int argc, char *argv[])
{
  pthread_t tid;
  int err;
  err = pthread_create(&tid, NULL, mythread, NULL);
  if (err < 0) {
    printf("create my thread failed\n");
    return -1;
  }
  int i = 0;
  for (i = 0; i < 10; ++i) {
    printf("In main thread there is %d\n", i);
    usleep(100);
  }
  interpeter = 1;
  sleep(10);
  return 0;
}

9 pthread~passstruct~.c

将一个结构体通过pthread~create~()的参数传给副进程，注意在副进程中的 结构体转化

#include "apue.h"

struct student {
  int age;
  char name[10];
  char subject[10];
};

void *thread_fun(void *stu)
{
  printf("In the constuction we have age : %d, name : %s, and subject %s.\n", ((struct  student *)stu)->age,((struct student *)stu)->name, ((struct student *)stu)->subject);
  return (void *)0;
}

int main( )
{
  pthread_t tid;
  int err;
  void * val;

  struct student stu;
  stu.age = 20;
  memcpy(stu.name, "xiang", 10);
  memcpy(stu.subject, "phyics", 10);

  err = pthread_create(&tid, NULL, thread_fun, (void *)&stu);
  if (err != 0) {
    printf("the new thread is failed to create\n");
    return  0;
  }
  pthread_exit(val);
  return 0;
}

10 pthread~stackattr~.c

在系统支持的条件下，获取栈的大小，并作出调整

#include "apue.h"

pthread_attr_t attr;

void *thread_fun(void *arg){

  size_t stacksize;

#ifdef _POSIX_THREAD_ATTR_STACKSIZE
  pthread_attr_getstacksize(&attr, &stacksize);
  printf("new thread stack size is %d \n", (int)stacksize );  //获取默认栈大小
  //更改 has to be greater than 16384, otherwise will be default
  pthread_attr_setstacksize(&attr, 100000);
  pthread_attr_getstacksize(&attr, &stacksize);
  printf("new thread stack size is %d \n", (int)stacksize );  //获取设置栈大小
#endif // _POSIX_THREAD_ATTR_STACKSIZE


  return (void *)1;
}


int main(int argc, char *argv[])
{
  pthread_t tid;
  int err;

  pthread_attr_init(&attr);

  //设置为可连接的分离属性
  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);

  //check if system support this
#ifdef _POSIX_THREAD_ATTR_STACKSIZE
  pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN);
#endif // _POSIX_THREAD_ATTR_STACKSIZE

  err = pthread_create(&tid, &attr, thread_fun, NULL);
  if (err) {
    printf("create new thread failed \n");
    return 0;
  }
  pthread_join(tid ,NULL);
  return 0;
}

Stoket

Git

tips

Raw 文件
git rm --cached file, will only delete it in git, but still in my local directory

Git installation in Linux

  1. sudo apt install git

  2. local configuration

git  config --global user.name "username1"
git  config --global user.email "email1"

git config --list

  1. in local terminal
ssh-keygen -t rsa -C "email2"

and then just all enter as default warming: email1 == email2

Webconfig

1. go to Fold Docu1, and in terminal git init to create local  repository
2. apply github count with:
   Email: email3
   Username: username3
   Password:xxxx
3. in setting add ssh key from local document: ./ssh/id_rsa.pub
4. create web repository with name Docu2
   Warming: Docu1 == Docu2

Connection

1. in local computer Docu1, create our files and prepare to push to
   Github
2. git add && git commit -m ""
3. git remote add origin HTTPS/SSH(of the created web repository)
   warming: with  HTTPS will be ask the Username:username3 and
   password:xxxx every time for the push, but SSH note
4. git push -u origin master
5. username3 and xxxx if necessary
6. later push it only use git push origin master

Magit

C-x g  : open the git buffer
S or s : to stage
C      : to commit 
C-c C-c : to finish commit
P and p to push

Git branch

git branch 创建development分支

branch 创建 新分支
创建新的分支： git branch development
带着全部家当去新的分支： git checkout development
git add -A 
git commit -m "development"
git push -u origin development

git merge 可以 merge mybranch分支到master分支

merge 融合分支
如果此时只有development分支改变，可以直接回到master, 把development分支
merge 过来   git merge development

git checkout master
git pull origin master
git branch --merged
git merge development
git push origin master

删除mybranch分支

git branch --merged
git branch -d mybrauch
git branch -a 
git push origin --delete mybrauch

git rm

  1. git rm --cached file

    编辑当前文件后，已提交(已 add),想撤出索引 ：    git rm --cached  file
after that, I can check the delete file with git status or git diff --cached.

  2. recover after git rm

    if I want , I can git add * to call all back again, but nothing to commit

  3. confirm to delete file in local directory

    if I ready want to delete this,
using rm file  delete the file in local directory, 
but git status and diff --cached remands this still, 
only after commit, there's no signal for the deleted file anymore.

  4. recover after delete in local directory

    git reflog
git reset --hard ID

git multi commit

commit 添加提交 和上次commit提交融合，不产生新的提交记录： git commit --amend

remote branch

git checkout -t origin/ui-mockup

commands to recover

after only save

git diff can see the different comparing to last time commit git checkout -- file git diff: NULL, file has been recovered

after git add file

git diff dit diff :NULL git diff --cached can see the different comparing to the last time commit git reset HEAD file git diff -- cached : NULL git checkout -- file file has been recovered

after git commit file

编辑后，强制回到最近一次添加索引的版本：        git reset --hard HEAD
编辑后，强制回到最近倒数第二次添加索引的版本：   git reset --hard HEAD~
编辑后，强制回到最近倒数第n次添加索引的版本：    git reset --hard HEAD~n

如果将HEAD换成对应的ID， 也可以回到之前相应的版本。 但是如果想再回去，
又没有记住之前的ID， 可以用，       git reflog 查询.

GWDG

  1. as student of Göttingen send email to support@gwdg.de with uni email, asking for freischaltung of cloud server
  2. got https://gwdg.de Dienst-> GWDG cloud server -> self service create Instance if with my ssh, the connect can be without password, but still need to aktiv
  3. where the instance is created, use the VNS to aktiv the konto, remember to save the password ssh cloud@ip

Google cloud

Certificate

  • First generate the self-singed certificate: Set CN to localhost,

    openssl req -new -x509 -nodes -keyout key.pem -sha256 -days 365 -out cert.pem
sudo cp cert.pem /etc/pki/ca-trust/source/anchors/
sudo update-ca-trust

  • First generate a new key, and Then create a CSR from it:

    openssl genrsa -out test.key 2048
openssl req -new -key test.key -out test.csr

  • creat extenation file test.ext, for domain name or DNS

    1 authorityKeyIdentifier=keyid,issuer
2 basicConstraints=CA:FALSE
3 keyUsage =digitalSignature, nonRepudiation, keyEncipherment, dataEncipherment
4 subjectAltName = @alt_names
5
6 [alt_names]
7 DNS.1 = localhost
8 DNS.2 = test.dev

  • Create a new signed certificate for extended information

    openssl x509 -req -in test.csr -CA cert.pem -CAkey key.pem -CAcreateserial \
-out test.crt -days 365 -sha256 -extfile test.ext

  • signed by Let's Encrypt

    sudo certbot certonly --standalone

  • DONe

Problem

System limit for number of file watchers reached

sudo sysctl -w fs.inotify.max~userwatches~=100000 reboot

ls

Docker

sudo docker rm $(sudo docker ps -aq)
sudo docker rmi $(sudo docker images -aq)

opencv

sudo cmake -DCMAKE~INSTALLPREFIX~:PATH=/home/si/Dokumente/opencv/libopencv .. make make install export LD~LIBRARYPATH~=$LD~LIBRARYPATH~:/home/si/Dokumente/opencv/libopencv/lib

Warp

Ctrl f move cousur to left, accept the auto complete Ctrl N next block Ctrl P provious block