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  1. bash - What are the special dollar sign shell variables ... - Stack ...

    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 which …

  2. Meaning of $? (dollar question mark) in shell scripts

    Aug 1, 2019 · What does echo $? mean in shell programming? true echo $? # echoes 0 false echo $? # echoes 1 From the manual: (acessible by calling man bash in your shell) ? Expands to the exit status …

  3. bash - What is the purpose of "&&" in a shell command? - Stack …

    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 only found in …

  4. What does 'set -e' mean in a Bash script? - Stack Overflow

    By default, Bash does not do this. This default behavior is exactly what you want if you are using Bash on the command line you don't want a typo to log you out! But in a script, you really want the …

  5. bash - Shell equality operators (=, ==, -eq) - Stack Overflow

    If not quoted, it is a pattern match! (From the Bash man page: "Any part of the pattern may be quoted to force it to be matched as a string."). Here in Bash, the two statements yielding "yes" are pattern …

  6. linux - What does $@ mean in a shell script? - Stack Overflow

    Apr 3, 2012 · What does a dollar sign followed by an at-sign (@) mean in a shell script? For example: umbrella_corp_options $@

  7. What's the difference between <<, <<< and < < in bash?

    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 whenever that …

  8. bash - Difference between >> and - Unix & Linux Stack Exchange

    In general, in bash and other shells, you escape special characters using \. So, when you use echo foo >\> what you are saying is "redirect to a file called > ", but that is because you are escaping the …

  9. How do I execute a bash script in Terminal? - Stack Overflow

    Mar 9, 2018 · I have a bash script like: #!/bin/bash echo Hello world! How do I execute this in Terminal?

  10. arguments - What is $@ in Bash? - Stack Overflow

    Oct 10, 2010 · I reckon that the handle $@ in a shell script is an array of all arguments given to the script. Is this true? I ask because I normally use search engines to gather information, but I can't …