* module/ice-9/ftw.scm (errno-if-exception): New macro.
(file-system-fold): Add an `error' parameter. Wrap `opendir' and STAT
calls in `errno-if-exception' and call ERROR when appropriate.
(file-system-tree): Provide an `error' procedure. Return #f when
FILE-NAME is unreadable.
(scandir): Provide an `error' procedure.
* test-suite/tests/ftw.test (%top-builddir): New variable.
(make-file-tree, delete-file-tree): New procedures.
(with-file-tree): New macro.
("file-system-fold"): Update tests to add an `error' procedure.
["ENOENT", "EACCES", "dangling symlink and lstat", "dangling symlink
and stat"]: New tests.
("file-system-tree")["ENOENT"]: New test.
("scandir")["EACCES"]: New test.
* doc/ref/misc-modules.texi (File Tree Walk): Update `file-system-fold'
documentation.
* module/ice-9/ftw.scm (scandir)[leaf]: Only add NAME when RESULT is a
pair.
[down]: Ignore RESULT.
Start with #f instead of the empty list.
* test-suite/tests/ftw.test ("scandir")["flat file"]: New test.
* doc/ref/misc-modules.texi (File Tree Walk): Update `scandir'
documentation accordingly.
Suggested by Nala Ginrut <nalaginrut@gmail.com>.
* module/ice-9/ftw.scm (scandir): New procedure.
* test-suite/tests/ftw.test ("scandir"): New test prefix.
* doc/ref/misc-modules.texi (File Tree Walk): Document `scandir'.
* module/ice-9/ftw.scm (file-system-fold, file-system-tree): New
procedures.
* test-suite/tests/ftw.test (%top-srcdir, %test-dir): New variables.
("file-system-fold", "file-system-tree"): New test prefixes.
* doc/ref/misc-modules.texi (File Tree Walk): Document
`file-system-tree' and `file-system-fold'.
* libguile/continuations.c (continuation_mark): Mark the vm
continuations.
* libguile/vm.c (vm_cont_mark): Fix the marking function.
(vm_mark): Fix this one too -- the size is a number of STACKITEMS,
which we foolishly assume are the same size as SCM.
* test-suite/tests/ftw.test: Make our stat hacks verifyable without
assuming that they are interpreted.
* test-suite/tests/r5rs_pitfall.test: Re-indent.
