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Let sleep(1) handle fractions of a second (up to nanosecond).

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This is a conservative change.  It does the same thing in weird
cases like the old one.  For example, 'sleep abcd' still sleeps
for zero seconds.  `sleep 10.a' and `sleep 10.05aa' do the best
and not abort (ie: 10.a == 10 seconds, 10.05a == 10.05 seconds).
This commit is contained in:
Ruslan Ermilov 1999-10-01 07:53:40 +00:00
parent 3196c2972d
commit ac14c3115f
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=51835
2 changed files with 72 additions and 12 deletions
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24
bin/sleep/sleep.1
View File

@ -42,7 +42,7 @@
.Nm sleep
.Nd suspend execution for an interval of time
.Sh SYNOPSIS
.Nm sleep
.Nm
.Ar seconds
.Sh DESCRIPTION
The
@ -50,17 +50,27 @@ The
command
suspends execution for a minimum of
.Ar seconds .
.Nm Sleep
is used to schedule the execution of other commands (see
.Sx EXAMPLES
below).
.Pp
If the
.Nm
command receives a signal, it takes the standard action.
.Sh IMPLEMENTATION NOTES
The
.Dv SIGALRM
signal is not handled specially by this implementation.
.Pp
The
.Nm
command will accept and honor a non-integer number of specified seconds
.Po
with a
.Ql \&.
character as a decimal point
.Pc .
.Bf Sy
This is a non-portable extension, and its use will nearly guarantee that
a shell script will not execute properly on another system.
.Ef
.Sh DIAGNOSTICS
The
.Nm
@ -110,9 +120,7 @@ when the file is found, then another portion processing
is done courteously by sleeping for 70 seconds in between each
awk job.
.Sh SEE ALSO
.Xr at 1 ,
.Xr nanosleep 2 ,
.Xr sleep 3
.Xr nanosleep 2
.Sh STANDARDS
The
.Nm

60
bin/sleep/sleep.c
View File

@ -45,8 +45,11 @@ static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
void usage __P((void));
@ -56,22 +59,71 @@ main(argc, argv)
int argc;
char *argv[];
{
int ch, secs;
struct timespec time_to_sleep;
long l;
int ch, neg;
char *p;
while ((ch = getopt(argc, argv, "")) != -1)
switch(ch) {
case '?':
default:
usage();
/* NOTREACHED */
}
argc -= optind;
argv += optind;
if (argc != 1)
if (argc != 1) {
usage();
/* NOTREACHED */
}
p = argv[0];
/* Skip over leading whitespaces. */
while (isspace((unsigned char)*p))
++p;
/* Check for optional `+' or `-' sign. */
neg = 0;
if (*p == '-') {
neg = 1;
++p;
}
else if (*p == '+')
++p;
/* Calculate seconds. */
if (isdigit((unsigned char)*p)) {
l = strtol(p, &p, 10);
if (l > INT_MAX) {
/*
* Avoid overflow when `seconds' is huge. This assumes
* that the maximum value for a time_t is >= INT_MAX.
*/
l = INT_MAX;
}
} else
l = 0;
time_to_sleep.tv_sec = (time_t)l;
/* Calculate nanoseconds. */
time_to_sleep.tv_nsec = 0;
if (*p == '.') { /* Decimal point. */
l = 100000000L;
do {
if (isdigit((unsigned char)*++p))
time_to_sleep.tv_nsec += (*p - '0') * l;
else
break;
} while (l /= 10);
}
if (!neg && (time_to_sleep.tv_sec > 0 || time_to_sleep.tv_nsec > 0))
(void)nanosleep(&time_to_sleep, (struct timespec *)NULL);
if ((secs = atoi(*argv)) > 0)
(void)sleep(secs);
exit(0);
}