Wikipedia says that
dash executes faster than
bash. My question is, if I set
dash, will all scripts that use
/bin/sh in their shebang line that was intended for
bash work under
No, not all scripts intended for bash work with dash. A number of 'bashism' will not work in dash, such as C-style for loops and the double-bracket comparison operators. If you have a set of bash scripts that you want to use for dash, you may consider using checkbashisms. This tool will check your script for bash-only features that aren't likely to work in dash.
Not even sh scripts are compatible with dash. Pkgsrc's bootstrap, par example.