No, there’s no csh here (for good reason), nor Plan 9 rc (for now).
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+Shell snippets that run with GNU bash and/or a Korn Shell (ksh93, mksh, pdksh).
+Please document exact requirements / restrictions.
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+Shell snippets that require GNU bash.
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+Shell snippets that require mksh.
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+Shell snippets that run with a POSIX shell.
+GNU bash, dash, AT&T ksh93, mksh. Maybe pdksh, posh, zsh in “emulate sh” mode.
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+Shell snippets for the Z Shell.