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标题: shell请教read,wait控制多线程 [打印本页]

作者: illfar 时间: 2012-06-12 16:50
标题: shell请教read,wait控制多线程
现在有一个例子，但是跑下来发现，程序无法结束，或者说退出
请高手指点

代码
# !/bin/bash

function a_sub {
sleep 3
}

tmp_fifofile="/tmp/$$.fifo"
mkfifo $tmp_fifofile
exec 6<>$tmp_fifofile
rm $tmp_fifofile

thread=5
for((i=0;i<$thread;i++)); do
echo >&6
done&

for((i=0;i<11;i++ )); do
read -u6
{
a_sub && {
echo " a_sub is finished "
} || {
ech " sub error "
}
echo >&6
}&

done

wait
exec 6>&-

exit 0

sh -x 的结果如下：

$ sh -x sample.sh
+ tmp_fifofile=/tmp/7300.fifo
+ mkfifo /tmp/7300.fifo
+ exec
+ rm /tmp/7300.fifo
+ thread=5
+ (( i=0 ))
+ (( i<5 ))
+ echo
+ (( i++ ))
+ (( i<5 ))
+ echo
+ (( i=0 ))
+ (( i<11 ))
+ read -u6
+ (( i++ ))
+ (( i<5 ))
+ echo
+ a_sub+ (( i++ ))

+ sleep 3
+ (( i<11 ))
+ read -u6
+ (( i++ ))
+ (( i<5 ))
+ echo
+ a_sub
+ sleep 3
+ (( i++ ))
+ (( i<11 ))
+ read -u6
+ (( i++ ))
+ (( i<5 ))
+ echo
+ (( i++ ))
+ (( i<11 ))
+ read -u6
+ a_sub
+ sleep 3
+ (( i++ ))
+ (( i<5 ))
+ (( i++ ))
+ (( i<11 ))
+ read -u6
+ a_sub
+ sleep 3
+ (( i++ ))
+ (( i<11 ))
+ a_sub
+ read -u6
+ sleep 3
+ echo ' a_sub is finished '+ echo ' a_sub is finished '

a_sub is finished
a_sub is finished
+ echo
+ echo
+ (( i++ ))
+ a_sub
+ (( i<11 ))
+ sleep 3
+ read -u6
+ (( i++ ))
+ (( i<11 ))+ a_sub

+ sleep 3
+ read -u6
+ echo ' a_sub is finished '
a_sub is finished
+ echo ' a_sub is finished '
+ echo
a_sub is finished
+ echo
+ (( i++ ))
+ (( i<11 ))
+ a_sub
+ read -u6
+ sleep 3
+ (( i++ ))
+ (( i<11 ))
+ read -u6
+ a_sub
+ sleep 3
+ echo ' a_sub is finished '
a_sub is finished
+ echo
+ a_sub
+ sleep 3+ (( i++ ))

+ (( i<11 ))
+ read -u6
+ echo ' a_sub is finished '
a_sub is finished
+ echo
+ echo ' a_sub is finished '
a_sub is finished
+ echo
+ a_sub
+ (( i++ ))
+ sleep 3+ (( i<11 ))

+ wait
+ echo ' a_sub is finished '
a_sub is finished
+ echo
+ echo ' a_sub is finished '
a_sub is finished
+ echo
+ echo ' a_sub is finished '
a_sub is finished
+ echo
+ echo ' a_sub is finished '
a_sub is finished
+ echo
这里停止了

作者: waker 时间: 2012-06-13 08:09
thread=7

作者: illfar 时间: 2012-06-14 08:35
回复 2# waker

什么意思啊
应该如何修改阿

作者: illfar 时间: 2012-06-14 14:54
thread=1的话，就没有问题了

为什么阿

作者: Honey-pot 时间: 2012-06-14 15:45
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作者: illfar 时间: 2012-06-14 16:12
回复 5# Honey-pot

可惜，猜错了

作者: Honey-pot 时间: 2012-06-14 16:27
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