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 …

Dec 22, 2010 · $ command one && command two the intent is to execute the command that follows the && only if the first command is successful. This is idiomatic of Posix shells, and not …

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 …

Modern shells such as Bash and Zsh have inherited this construct from Ksh, but it is not part of the POSIX specification. If you're in an environment where you have to be strictly POSIX …

Feb 10, 2010 · How do I compare a variable to a string (and do something if they match)?

Oct 4, 2008 · Related discusions: bash for loop: a range of numbers and unix.stackexchange.com - In bash, is it possible to use an integer variable in the loop control of a for loop?

Jul 17, 2013 · It doesn't mean anything "in bash". [ runs a command called test. -ne is an argument to the test command, not to bash, and you can find its documentation in man test.

Apr 18, 2012 · 59 $ man bash -e file True if file exists. -f file True if file exists and is a regular file. A regular file is something that isn't a directory, symlink, socket, device, etc.

Is there any comprehensive list of characters that need to be escaped in Bash? Can it be checked just with sed? In particular, I was checking whether % needs to be escaped or not. I tried echo …

Nov 24, 2012 · Ubuntu 16.04 actually has an executable for it at /usr/bin/[ provided by coreutils, but the bash built-in version takes precedence. Nothing is altered in the way that Bash parses …