3 ms·

Yes, you probably want su rather than su -. He uses sh only to run some command but that's obviously superflous, he should just use su -c. The fact that he sour

by 4ad 14y ago

Yes, you probably want su rather than su -. He uses sh only to run some command but that's obviously superflous, he should just use su -c. The fact that he sources the user's profile is hilarious. The fact that this remarkably poor and trivial article made it to the HN front page is sad.

StavrosK 14y ago
> The fact that he sources the user's profile is hilarious. Why is that? Also, if all he wants is to run a command, why not use sudo? Isn't that what sudo is supposed to do (i.e. pretty much what su -c does)?
- 4ad 14y ago
  > Why is that? Because he just did a login: silver:aram$ sudo su aram -c 'echo $PATH' /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games silver:aram$ sudo su - aram -c 'echo $PATH' .:/home/aram/bin:/home/aram/bin/linux:/home/aram/bin/linux/amd64:/home/aram/bin/linux/386:/home/aram/go/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/games:/usr/local/bin:/usr/local/sbin:/home/aram/plan9/bin silver:aram$ sudo su - aram -c '. ~/.profile; echo $PATH' .:/home/aram/bin:/home/aram/bin/linux:/home/aram/bin/linux/amd64:/home/aram/bin/linux/386:/home/aram/go/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/games:/usr/local/bin:/usr/local/sbin:/home/aram/plan9/bin > why not use sudo? Isn't that what sudo is supposed to do (i.e. pretty much what su -c does)? Sure, he could have used sudo.
  - runlevel1 14y ago
    Careful adding '.' to your $PATH, particularly as the first item. It makes it awful easy to execute something you forgot/didn't know was in the current working directory. UPenn gives a pretty good explanation here: http://www.seas.upenn.edu/cets/answers/dot-path.html http://www.seas.upenn.edu/cets/answers/dot-path.html The security issue is most relevant on multi-user systems, including hosted services (e.g. a web server with an upload feature and misconfigured umask). I don't do it on my personal system either because I am my own worst enemy and am frequently saved by the Unix "rule of least surprise." It's the usual convenience/risk balance. To each his own.

by 4ad 14y ago

StavrosK 14y ago

> The fact that he sources the user's profile is hilarious. Why is that? Also, if all he wants is to run a command, why not use sudo? Isn't that what sudo is supposed to do (i.e. pretty much what su -c does)?

4ad 14y ago
> Why is that? Because he just did a login: silver:aram$ sudo su aram -c 'echo $PATH' /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games silver:aram$ sudo su - aram -c 'echo $PATH' .:/home/aram/bin:/home/aram/bin/linux:/home/aram/bin/linux/amd64:/home/aram/bin/linux/386:/home/aram/go/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/games:/usr/local/bin:/usr/local/sbin:/home/aram/plan9/bin silver:aram$ sudo su - aram -c '. ~/.profile; echo $PATH' .:/home/aram/bin:/home/aram/bin/linux:/home/aram/bin/linux/amd64:/home/aram/bin/linux/386:/home/aram/go/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/games:/usr/local/bin:/usr/local/sbin:/home/aram/plan9/bin > why not use sudo? Isn't that what sudo is supposed to do (i.e. pretty much what su -c does)? Sure, he could have used sudo.
- runlevel1 14y ago
  Careful adding '.' to your $PATH, particularly as the first item. It makes it awful easy to execute something you forgot/didn't know was in the current working directory. UPenn gives a pretty good explanation here: http://www.seas.upenn.edu/cets/answers/dot-path.html http://www.seas.upenn.edu/cets/answers/dot-path.html The security issue is most relevant on multi-user systems, including hosted services (e.g. a web server with an upload feature and misconfigured umask). I don't do it on my personal system either because I am my own worst enemy and am frequently saved by the Unix "rule of least surprise." It's the usual convenience/risk balance. To each his own.