The command is date To customise the output there are a myriad of options available, see date –help for a list. For example, date ‘+%A %W %Y %X’ gives Tuesday 34 2013 08:04:22 which is the name of the day of the week, the week number, the year and the time.
Just do: SET You can also do SET prefix to see all variables with names starting with prefix. For example, if you want to read only derbydb from the environment variables, do the following: set derby …and you will get the following: DERBY_HOME=c:\Users\amro-a\Desktop\db-derby-10.10.1.1-bin\db-derby-10.10.1.1-bin
Use “$@” to represent all the arguments: for var in “$@” do echo “$var” done This will iterate over each argument and print it out on a separate line. $@ behaves like $* except that when quoted the arguments are broken up properly if there are spaces in them: sh test.sh 1 2 ‘3 4’ … Read more
Using Java 6 or later, the classpath option supports wildcards. Note the following: Use straight quotes (“) Use *, not *.jar Windows java -cp “Test.jar;lib/*” my.package.MainClass Unix java -cp “Test.jar:lib/*” my.package.MainClass This is similar to Windows, but uses : instead of ;. If you cannot use wildcards, bash allows the following syntax (where lib is … Read more
This will unstage all files you might have staged with git add: git reset This will revert all local uncommitted changes (should be executed in repo root): git checkout . You can also revert uncommitted changes only to particular file or directory: git checkout [some_dir|file.txt] Yet another way to revert all uncommitted changes (longer to … Read more
Simply type source ~/.bash_profile. Alternatively, if you like saving keystrokes, you can type . ~/.bash_profile.
You can specify formal arguments in rake by adding symbol arguments to the task call. For example: require ‘rake’ task :my_task, [:arg1, :arg2] do |t, args| puts “Args were: #{args} of class #{args.class}” puts “arg1 was: ‘#{args[:arg1]}’ of class #{args[:arg1].class}” puts “arg2 was: ‘#{args[:arg2]}’ of class #{args[:arg2].class}” end task :invoke_my_task do Rake.application.invoke_task(“my_task[1, 2]”) end # … Read more
Like this on all Microsoft OSes since 2000, and still good today: dir & echo foo If you want the second command to execute only if the first exited successfully: dir && echo foo The single ampersand (&) syntax to execute multiple commands on one line goes back to Windows XP, Windows 2000, and some … Read more
Use wc: wc -l <filename> This will output the number of lines in <filename>: $ wc -l /dir/file.txt 3272485 /dir/file.txt Or, to omit the <filename> from the result use wc -l < <filename>: $ wc -l < /dir/file.txt 3272485 You can also pipe data to wc as well: $ cat /dir/file.txt | wc -l 3272485 … Read more
Use this query: SELECT User FROM mysql.user; Which will output a table like this: +——-+ | User | +——-+ | root | +——-+ | user2 | +——-+ As Matthew Scharley points out in the comments on this answer, you can group by the User column if you’d only like to see unique usernames.