Classic technique (escape metacharacters): if[ \( $g -eq 1-a "$c"="123" \) -o \( $g -eq 2-a "$c"="456" \) ]then echo abc else echo efg fi I tried various tricks with '[[ ... ]]' without success - even escaping the…

Maybe one of the most used MySQL commands is SELECT, that is the way to stract the information from the database, but of course one does not need all the info inside a database, therefore one should limit the info coming out from the table, there is…

$ cat file START Unix Linux START Solaris Aix SCO 1. Join the lines following the pattern START without any delimiter. $ awk '/START/{if (NR!=1)print "";next}{printf $0}END{print "";}' file UnixLinux SolarisAixSCO 2. Join the lines fol…

find . -name "*.result.zip" | xargs -n 1 unzip - -P password -d ../ext_logs…

最近在做Windows shell extension 的开发工作,对shell extension handler的注册机制有点疑问,以下摘自MSDN:http://msdn.microsoft.com/en-us/library/windows/desktop/cc144067(v=vs.85).aspx Registering Shell Extension Handlers A Shell extension handler object must be registered befor…

In this lesson, we'll filter a list of objects based on multiple conditions and we'll use Ramda's allPass function to create a joint predicate from multiple, individual predicate functions. const R = require('ramda'); const { allPass, propEq, lte, pr…

Query Method MongoDB provides the db.collection.find() method to read documents from a collection. The db.collection.find() method returns a cursor to the matching documents. db.collection.find( <query filter>, <projection> ) For the db.collec…

Man page systemd.unit SYSTEMD.UNIT(5) systemd.unit SYSTEMD.UNIT(5) NAME systemd.unit - Unit configuration SYNOPSIS service.service, socket.socket, device.device, mount.mount, automount.automount, swap.swap, target.target, path.path, timer.timer, snap…

http://www.grymoire.com/unix/sed.html Quick Links - NEW Sed Commands : label # comment {....} Block =- print line number a \- Append b label- Branch c \ - change dand D- Delete gand G- Get hand H- Hold i \- Insert l- Look nand N- Next pand P- Print q…

总结 1.插入数据 db.inventory.insertMany( [ { item: "journal", instock: [ { warehouse: "A", qty: 5 }, { warehouse: "C", qty: 15 } ] }, { item: "notebook", instock: [ { warehouse: "C", qty: 5 } ] }, { item: "…