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Scripts without shebang

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# 1  
Old 08-30-2012
They will run in the shell of the user who executed it.
So if user uses /bin/bash, the script will be executed in that shell.

No, that does not mean it will work in every shell, it probably won't.
# 2  
Old 08-30-2012
Quote:
Originally Posted by Peasant
They will run in the shell of the user who executed it.
So if user uses /bin/bash, the script will be executed in that shell.
That's incorrect. When an executable file's header/magic isn't recognized, it is passed to /bin/sh regardless of the user's shell.

Note that this behavior (falling back on /bin/sh) is only available through some library functions (execlp, execvp, execvpe) which wrap the execve(2) system call. Any code that tries to execute such a script using other means (such as directly invoking execve(2)) will fail.

Regards,
Alister
Last edited by alister; 08-30-2012 at 06:24 PM.. Reason: elaboration
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# 3  
Old 08-31-2012
Quote:
Originally Posted by alister
That's incorrect. When an executable file's header/magic isn't recognized, it is passed to /bin/sh regardless of the user's shell.
Is that correct?
I'm on FreeBSD (sorry don't know how to get version info). The login uses bash.
If I run a script containing only this line
Code:
[[ 1 == 1 ]] && echo yes || echo no

It results in (seems to use bash)
Code:
yes

If I enter a sh-shell with sh and run the script I get (seems to use sh)
Code:
[[: not found
no

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