netstat -a | grep ssh
pkg-config --list-all
source ~/.bash_profile
sudo tail -f /var/log/system.log
:w !sudo tee %
:w !sudo tee > /dev/null %
tty
ssh -v ## check ssh agent configuration- configuration tool for certain machine settings in System Preferences
sudo systemsetup -setremotelogin on
sudo systemsetup -setremotelogin off
sudo systemsetup -getremoteloginarbitrary TCP and UDP connections and listens listen port 22 then received message and display
sudo nc -l 22
connect 127.0.0.1 port 22 then send message
nc 127.0.0.1 22
Specifies that nc should just scan for listening daemons, without sending any data to them
nc -z host.example.com 20-30
netstat -an | grep 22
- need comments
sudo lsof -i -P | grep 22 launchd 1 root 96u IPv6 0x0d940bb0 0t0 TCP *:22 (LISTEN) launchd 1 root 99u IPv4 0x10b46abc 0t0 TCP *:22 (LISTEN)
eval ssh-agent
Agent pid 9700
**manipulates a domain**
launchctl list | grep ssh launchctl list com.openssh.ssh-agent
locale locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory LANG=POSIX LC_CTYPE=zh_CN.UTF-8 LC_NUMERIC="POSIX" LC_TIME="POSIX" LC_COLLATE="POSIX"
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[Running MacOS X without a GUI](http://bill.welliver.org/space/start/2017-05/running_macos_x_without_a_gui?PSESSIONID=db4b8ec9316fc49c989b)
- AT tasks
at atq at -c job
>/usr/lib/cron/jobs/
atrun
Execute the following command as root to enable atrun:
launchctl load -w /System/Library/LaunchDaemons/com.apple.atrun.plist
> com.apple.atrun.plist
/var/at/jobs Directory containing job files
/var/at/spool Directory containing output spool files
/var/at/lockfile Job-creation lock file.
- check route table
netstat -rn
>Routing tables
>
>Internet:
Destination Gateway Flags Refs Use Netif Expire
default 192.168.2.1 UGSc 215 0 en0
127 127.0.0.1 UCS 0 11 lo0
127.0.0.1 127.0.0.1 UH 191 12775916 lo0
169.254 link#5 UCS 0 0 en0
192.168.2 link#5 UCS 1 0 en0
192.168.2.1/32 link#5 UCS 1 0 en0
192.168.2.1 e8:fc:af:a2:40:70 UHLWIir 6 77 en0 1190
192.168.2.123/32 link#5 UCS 0 0 en0
192.168.2.255 ff:ff:ff:ff:ff:ff UHLWbI 0 7 en0
224.0.0/4 link#5 UmCS 1 0 en0
224.0.0.251 1:0:5e:0:0:fb UHmLWI 0 0 en0
255.255.255.255/32 link#5 UCS 0 0 en0
```route -n get default```
> route to: default
destination: default
mask: default
gateway: 192.168.2.1
interface: en0
flags: <UP,GATEWAY,DONE,STATIC,PRCLONING>
recvpipe sendpipe ssthresh rtt,msec rttvar hopcount mtu expire
0 0 0 0 0 0 1500 0
#### configuring your network in terminal ####
- Turning Wi-Fi on or off
networksetup -getairportpower networksetup -setairportpower
- Setting the AirPort network
networksetup -getairportnetwork networksetup -setairportnetwork [password]
- Managing preferred wireless networks
networksetup -listpreferredwirelessnetworks networksetup -addpreferredwirelessnetworkatindex [password] networksetup -removepreferredwirelessnetwork networksetup -removeallpreferredwirelessnetworks <device name
- Additional options
/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport airport -c airport -I airport -S
**change terminal title**
```echo -n -e "\033]0;YOUR TITLE HERE\007"```
### How do I solve the problem that the terminal display "Failed to set locale, defaulting to C warning " ###
To set i18n stuff CentOS/Fedora and RedHat Enterprise Linux call a special script called /etc/profile.d/lang.sh. Make sure this file exist in your system:
```$ ls -l /etc/profile.d/lang.sh```
If file exist just call it:
```$ source /etc/profile.d/lang.sh```
Verify that LANG and LC_* shell variable are set:
$ echo "$LANG" $ echo "$LC_CTYPE"
### CentOS start command & enable service on boot ###
systemctl start nginx systemctl enable nginx
### Check Linux OS Information by terminal ###
```shell
cat /etc/*-release
lsb_release -a
uname -a
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