Some useful linux commands and Techniques

Some useful linux commands and tips! $ Represents the last string of the previous command. It is used to simplify input !!, Indicates the previous command. If you do not want to press the downward direction key + press enter, you can use this ^ old ^ new to replace the old in the previous command with new, suitable for places where the entire command is long but the command transformation is not big; du-s * | sort-n | tail, display the Ten files or folders that occupy the most disk space in the current directory date-d @ 123, convert the timestamp to the date, which takes into account the time zone> test, create a test empty file, which is shorter than touch man ascii/unicode, and view the ascii code sort-nk + 4. sort the files in curl ifconfig by column 4th in ascending order. me. When you are on the Intranet, check the ip address and port of the local machine on the external network. The usage is as follows: curl ifconfig. me/ip, curl ifconfig. me/port to view the help documentation, not only man, but also info. Shutdown-k. It sends a shutdown warning to all users, pretending to shut down, but not actually shutting down. Vim hexadecimal display command: %! If timeout is not defined in xxdmenu. lst, halt may not be automatically started when the startup Item is selected. Therefore, when you modify menu. lst on the remote server, remember to add timeout at the beginning. Otherwise, you can only manually press enter at the data center. To update the kernel on suselinux, modify the version information in Makefile & make menuconfig & make modules & make modules_install & make install & modify menu. default in lst (otherwise the old kernel will be started ). If the order is incorrect, the init ramfile or startup failure may occur. In this case, you can first remove all the new kernel options in menu. lst (if not removed, menu. lst will not be updated automatically), and then re-make modules_install & make install.