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.
When you try to execute a program in unix (one with the executable bit set), the operating system will look at the first few bytes of the file. These form the so-called "magic number", which can be used to decide the format of the program and how to execute it.
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.
Related question is "Datetime To Unix timestamp", but this question is more general. I need Unix timestamps to solve my last question. My interests are Python, Ruby and Haskell, but other approac...
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 ...
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".
I know that using ls -l "directory/directory/filename" tells me the permissions of a file. How do I do the same on a directory? I could obviously use ls -l on the directory higher in the hierarchy...
