1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
|
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# setalrm - set a timer to fire in N seconds and send SIGALRM to the shell
#
# usage: setalrm [-c] N
#
# -c means to reset the trap on ALRM if the timer is canceled
#
# If N = 0, we cancel any pending alarm by killing the background timeout
# process. Any value greater than 0 sets a timeout for N seconds. Values
# of N less than zero are errors.
declare -i alrmpid=
setalrm()
{
local untrap=
local setalrm_usage="setalrm: usage: setalrm [-c] N"
while getopts c opt; do
case $opt in
c) untrap=1 ;;
*) echo "$setalrm_usage" >&2 ; return 2;;
esac
done
shift $(( $OPTIND - 1 ))
if [[ -z $1 ]]; then
echo "$setalrm_usage" >&2
return 2
fi
if (( $1 < 0 )); then
echo "setalrm: timeout must be greater than zero" >& 2
return 2
fi
if [[ $1 -eq 0 ]] && [[ -n "$alrmpid" ]]; then
kill -TERM $alrmpid ; es=$?
alrmpid=
if [ -n "$untrap" ]; then
trap - ALRM # caller saves if desired
fi
return $es
fi
# setting alarm
{ trap - ALRM ; sleep $1; kill -ALRM $$; } &
alrmpid=$!
return 0
}
|
