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 …

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 …

It depends on the Test Construct around the operator. Your options are double parentheses, double brackets, single brackets, or test. If you use ((…)), you are testing arithmetic equality …

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...

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 …

Nov 23, 2009 · 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 …

I am trying to figure out what is the usage of this command: echo < a.txt According to text book it should redirect a programs standards input. Now I am redirecting a.txt to echo but instead of

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 …

May 5, 2011 · How can I recursively find all files in current and subfolders based on wildcard matching?

Nov 9, 2012 · I have two directories with the same list of files. I need to compare all the files present in both the directories using the diff command. Is there a simple command line option …