
The UNIX® Standard | www.opengroup.org
May 22, 2025 · 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 …
What does the line "#!/bin/sh" mean in a UNIX shell script?
Sep 10, 2011 · 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 …
What are the special dollar sign shell variables? - Stack Overflow
Sep 14, 2012 · In Bash, there appear to be several variables which hold special, consistently-meaning values. For instance, ./myprogram &; echo $! will return the PID of the process …
unix - what does '$?' mean in a shell script? - Stack Overflow
Oct 5, 2012 · I came across a shell script that contains a statement like, if [ $val -eq $? ] What does $? mean here?
git - How to change line-ending settings - Stack Overflow
Is there a file or menu that will let me change the settings on how to deal with line endings? I read there are 3 options: Checkout Windows-style, commit Unix-style Git will convert LF to CRLF …
How can I send an email through the UNIX mailx command?
Feb 17, 2010 · 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 …
unix - How to move a running process to background - Stack …
I have a terminal connected to an external machine through ssh and have a process running in it. Is it possible move the execution to the background, so that I can close the ssh connection …
What is the proper way to exit a command line program?
2 Take a look at Job Control on UNIX systems If you don't have control of your shell, simply hitting ctrl + C should stop the process. If that doesn't work, you can try ctrl + Z and using the jobs …
Boolean operators ( &&, -a, ||, -o ) in Bash - Stack Overflow
Dec 8, 2013 · What is the difference between the &&, ||, -a, and -o Unix operators? What are the restrictions on the usage of both types? Is it simply that the && and || operators should be used ...
Difference between CR LF, LF and CR line break types
Oct 12, 2009 · I'd like to know the difference (with examples if possible) between CR LF (Windows), LF (Unix) and CR (Macintosh) line break types.