examples/loadables/sleep.c

   1 /*
   2  * sleep -- sleep for fractions of a second
   3  *
   4  * usage: sleep seconds[.fraction]
   5  */
   6
   7 /*
   8    Copyright (C) 1999-2020 Free Software Foundation, Inc.
   9
  10    This file is part of GNU Bush.
  11    Bush is free software: you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation, either version 3 of the License, or
  14    (at your option) any later version.
  15
  16    Bush is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with Bush.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "config.h"
  26
  27 #include "bushtypes.h"
  28
  29 #if defined (TIME_WITH_SYS_TIME)
  30 #  include <sys/time.h>
  31 #  include <time.h>
  32 #else
  33 #  if defined (HAVE_SYS_TIME_H)
  34 #    include <sys/time.h>
  35 #  else
  36 #    include <time.h>
  37 #  endif
  38 #endif
  39
  40 #if defined (HAVE_UNISTD_H)
  41 #include <unistd.h>
  42 #endif
  43
  44 #include <stdio.h>
  45 #include "chartypes.h"
  46
  47 #include "shell.h"
  48 #include "builtins.h"
  49 #include "common.h"
  50
  51 int
  52 sleep_builtin (list)
  53 WORD_LIST       *list;
  54 {
  55         long    sec, usec;
  56         char    *ep;
  57         int     r, mul;
  58         time_t  t;
  59
  60         if (list == 0) {
  61                 builtin_usage();
  62                 return(EX_USAGE);
  63         }
  64
  65         /* Skip over `--' */
  66         if (list->word && ISOPTION (list->word->word, '-'))
  67                 list = list->next;
  68
  69         if (*list->word->word == '-' || list->next) {
  70                 builtin_usage ();
  71                 return (EX_USAGE);
  72         }
  73
  74         r = uconvert(list->word->word, &sec, &usec, &ep);
  75         /* Maybe postprocess conversion failures here based on EP */
  76
  77         if (r) {
  78                 fsleep(sec, usec);
  79                 QUIT;
  80                 return(EXECUTION_SUCCESS);
  81         }
  82
  83         builtin_error("%s: bad sleep interval", list->word->word);
  84         return (EXECUTION_FAILURE);
  85 }
  86
  87 static char *sleep_doc[] = {
  88         "Suspend execution for specified period.",
  89         ""
  90         "sleep suspends execution for a minimum of SECONDS[.FRACTION] seconds.",
  91         (char *)NULL
  92 };
  93
  94 struct builtin sleep_struct = {
  95         "sleep",
  96         sleep_builtin,
  97         BUILTIN_ENABLED,
  98         sleep_doc,
  99         "sleep seconds[.fraction]",
 100         0
 101 };