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 …

Oct 27, 2021 · $ 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 …

8 In bash, && and || have equal precendence and associate to the left. See Section 3.2.3 in the manual for details. So, your example is parsed as $ (echo this || echo that) && echo other And …

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 …

Sep 27, 2015 · What's the difference between <<, <<< and < < in bash?Here document << is known as here-document structure. You let the program know what will be the ending text, and …

Nitpicking The switches -a and -n are not strictly part of a bash if statement in that the if command does not process these switches. What are primaries? I call them "switches", but the bash …

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.

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

Jun 3, 2012 · 152 Quoting from man bash: -c string If the -c option is present, then commands are read from string. If there are arguments after the string, they are assigned to the positional …

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 …