;;; std/os.lisp --- OS interop definitions

 ;; UNIX only.

 ;;; Code:

 (in-package :std/os)

 (require 'sb-posix)

 (defun list-all-users ()

   "List all users via passwd. (uid gid name home shell comment)"

   (let ((r nil))

     (sb-posix:do-passwds (u r) 

       (push (list (sb-posix:passwd-uid u)

                   (sb-posix:passwd-gid u)

                   (sb-posix:passwd-name u)

                   (sb-posix:passwd-dir u)

                   (sb-posix:passwd-shell u)

                   (sb-posix:passwd-gecos u))

             r))

     r))

 (defun list-all-groups ()

   "List all groups. (gid name mem)"

   (let ((r nil))

   (sb-posix:do-groups (g r) (push (list (sb-posix:group-gid g)

                                         (sb-posix:group-name g)

                                         (sb-posix:group-mem g))

                                   r))))

 (defmacro with-umask (mask &body body)

   "Temporarily set the system-wide umask for the extent of BODY."

   (with-gensyms (umask)

     `(let ((,umask (sb-posix:umask ,mask)))

        (unwind-protect (progn ,@body)

          (sb-posix:umask ,umask)))))

 ;; (with-umask #o22 nil)

 (defmacro with-fd ((fvar fname &key (flags #.sb-posix:o-rdonly) (close t)) &body body)

   `(let* ((,fvar (sb-posix:open ,fname ,flags)))

      (unwind-protect (progn ,@body)

        ,@(when close `(sb-posix:close ,fvar)))))