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) 1999-2009 Free Software Foundation, Inc.
   9
  10    This file is part of GNU Bash.
  11    Bash 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    Bash 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 Bash.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "config.h"
  26
  27 #include "bashtypes.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 #define RETURN(x) \
  52         do { \
  53                 if (sp) *sp = sec; \
  54                 if (usp) *usp = usec; \
  55                 return (x); \
  56         } while (0)
  57
  58 int
  59 sleep_builtin (list)
  60 WORD_LIST       *list;
  61 {
  62         long    sec, usec;
  63
  64         if (list == 0) {
  65                 builtin_usage();
  66                 return(EX_USAGE);
  67         }
  68
  69         if (*list->word->word == '-' || list->next) {
  70                 builtin_usage ();
  71                 return (EX_USAGE);
  72         }
  73
  74         if (uconvert(list->word->word, &sec, &usec)) {
  75                 fsleep(sec, usec);
  76                 return(EXECUTION_SUCCESS);
  77         }
  78
  79         builtin_error("%s: bad sleep interval", list->word->word);
  80         return (EXECUTION_FAILURE);
  81 }
  82
  83 static char *sleep_doc[] = {
  84         "Suspend execution for specified period.",
  85         ""
  86         "sleep suspends execution for a minimum of SECONDS[.FRACTION] seconds.",
  87         (char *)NULL
  88 };
  89
  90 struct builtin sleep_struct = {
  91         "sleep",
  92         sleep_builtin,
  93         BUILTIN_ENABLED,
  94         sleep_doc,
  95         "sleep seconds[.fraction]",
  96         0
  97 };