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On Mon, Jun 20, 2011 at 08:39:00PM +1000, Adam Carter wrote: |
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> >> /bin/sh is a symlink to bash. |
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> > |
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> > Which runs as sh when run from the symlink. |
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> |
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> I dont understand. "runs as" usually means "runs under the user |
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> context" to me - are you saying bash has an sh compatibility mode? |
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Yes, from the bash man page: |
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If bash is invoked with the name sh, it tries to mimic the startup |
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behavior of historical versions of sh as closely as possible, while |
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conforming to the POSIX standard as well. When invoked as an interac‐ |
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tive login shell, or a non-interactive shell with the --login option, |
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it first attempts to read and execute commands from /etc/profile and |
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~/.profile, in that order. The --noprofile option may be used to |
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inhibit this behavior. When invoked as an interactive shell with the |
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name sh, bash looks for the variable ENV, expands its value if it is |
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defined, and uses the expanded value as the name of a file to read and |
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execute. Since a shell invoked as sh does not attempt to read and exe‐ |
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cute commands from any other startup files, the --rcfile option has no |
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effect. A non-interactive shell invoked with the name sh does not |
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attempt to read any other startup files. When invoked as sh, bash |
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enters posix mode after the startup files are read. |
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W |
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-- |
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Willie W. Wong wwong@××××××××××××××.edu |
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Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire |
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et vice versa ~~~ I. Newton |
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