Single UNIX Specification- “The Standard” The Single UNIX Specification is the standard in which the core interfaces of a UNIX OS are measured. The UNIX standard includes a rich feature set, and its core volumes are simultaneously the IEEE Portable Operating System Interface (POSIX) standard and the ISO/IEC 9945 standard.
I need to extract a certain section of this file (i.e. the data for a single database) and place it in a new file. I know both the start and end line numbers of the data that I want. Does anyone know a Unix command (or series of commands) to extract all lines from a file between say line 16224 and 16482 and then redirect them into a new file?
Since every Unix does things a little differently -- Solaris, Mac OS X, IRIX, BSD, and Linux all have their quirks -- POSIX is especially useful to those in the industry as it defines a standard environment to operate in.
From the man page: Sending mail To send a message to one or more people, mailx can be invoked with arguments which are the names of people to whom the mail will be sent. The user is then expected to type in his message, followed by an ‘control-D’ at the beginning of a line. In other words, mailx reads the content to send from standard input and can be redirected to like normal. E.g.: ls -l ...
The standard POSIX/Single Unix Specification shell is a very limited language which doesn't contain facilities for representing sequences (list or arrays) or associative arrays (also known as hash tables, maps, dicts, or objects in some other languages). This makes representing the result of parsing JSON somewhat tricky in portable shell scripts.
Explanation Unix system represent a point in time as a number. Specifically the number of seconds* since a zero-time called the Unix epoch which is 1/1/1970 00:00 UTC/GMT. This number of seconds is called "Unix timestamp" or "Unix time" or "POSIX time" or just "timestamp" and sometimes (confusingly) "Unix epoch".
Adding n seconds to 1970-01-01 will give you a UTC date because n – the Unix timestamp – is the number of seconds that have elapsed since 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970. In SQL Server 2016, you can convert one time zone to another using AT TIME ZONE. You need to specify the name of the time zone in Windows standard format:
The definition of unix time and the epoch date went through a couple of changes before stabilizing on what it is now. But it does not say why exactly 1/1/1970 was chosen in the end.