On Fri, Dec 23, 2016 at 12:57:48AM +1100, Andrew McGlashan wrote:
#!/usr/bin/env bash
please don't promote thet obnoxious brain-damage. it's bad enough seeing the #!/usr/bin/env disease on sites like stackexchange (where at least they have the excuse of catering to non-linux systems - and even there it's broken, because env isn't guaranteed to be in /usr/bin on all systems anyway) but bash will be /bin/bash on every linux system that exists, and always will be. there are lots of good reasons why abusing /usr/bin/env like this is a bad idea at: http://unix.stackexchange.com/questions/29608/why-is-it-better-to-use-usr-bi... (see also the Linked and Related Q&As on the RHS of the page) the one argument in favour of doing this (that the script will be run by the first matching interpreter found in the PATH) is both a blessing and a curse. at best it's a minor convenience. at worst, it's a potential security risk - it's not an accident or an oversight that every unix system since the #! line was invented DOESN'T search $PATH for the interpreter. one of the worst problems with doing it is that it breaks the ability to pass command-line options to the interpreter in the #! line - e.g. '#!/bin/bash -e' works, but with '#!/usr/bin/env bash -e' the '-e' is ignored by bash. this is bad enough for bash, but worse for other scripting languages where passing command-line options to the #! interpreter is routine (like sed, awk, perl) or required (like make, which requires '-f' on the #! line of an executable make script). also, env messes with ARGV[0] which can make the script difficult or impossible to find with ps '#!/usr/bin/env interpreter' - brought to you by the people who think that 'curl http://randomwebsite/path/to/script | sudo bash' is a good way to install software. craig -- craig sanders <cas@taz.net.au>