FAQ
Check out the redirection at the end of each command. 1>&2 redirects
the standard out of your child command to the standard error which then
appears in the parent shell. At the end the last & launches your
command into a background shell and then moves on to launch the next
command. The redirections don't care if the command ever terminates.

The result is that both commands are launched and the parent shell
terminates leaving the standard error attached to the terminal that the
parent was launched in.
On 03/27/2012 09:08 PM, bruce wrote:
marklapier at aol.com

hey mark....

what you have, appears to be pretty close to what i had... except my
tests never ended... the loops are infinite...

can i do a fpaste and have you take a look at what i have?

-btuce


On Tue, Mar 27, 2012 at 9:00 PM, Mark LaPierrewrote:
On 03/27/2012 05:25 PM, bruce wrote:

hi.

got a couple of test bash scripts.

dog.sh, cat.sh
each script runs the underlying php in an endless loop.

I'm trying to figure out how to run the scripts in parallel, from the
same parent shell script. something like:

test.sh


where dog.sh would be :
--------------------------------
while true
do
pgrep dog
if [ $? -ne 0 ]
then
/dog.php
fi
sleep 5
done

my current tests, run dog.sh, which runs the dog.php ... but the test
never gets to run cat.sh

thoughts/comments...

thanks
Hey Bruce,

Do you mean to run these subprograms in parallel or in series?

cat.sh
#! /bin/bash

CAT=0
until [ $CAT -eq 10 ]
do
echo "Inside a dog it's too dark to read. $CAT"
CAT=$[$CAT + 1]
sleep 2
done


dog.sh
#! /bin/bash

DOG=0
until [ $DOG -eq 10 ]
do
echo "Next to a dog a book is man's best friend. $DOG"
DOG=$[$DOG + 1]
sleep 2
done


test.sh
#! /bin/sh

/home/mlapier/test/dog.sh 1>&2&
/home/mlapier/test/cat.sh 1>&2&


[mlapier at mushroom test]$ ./test.sh
[mlapier at mushroom test]$ Next to a dog a book is man's best friend. 0
Inside a dog it's too dark to read. 0
Next to a dog a book is man's best friend. 1
Inside a dog it's too dark to read. 1
Next to a dog a book is man's best friend. 2
Inside a dog it's too dark to read. 2
Next to a dog a book is man's best friend. 3
Inside a dog it's too dark to read. 3
Next to a dog a book is man's best friend. 4
Inside a dog it's too dark to read. 4
Next to a dog a book is man's best friend. 5
Inside a dog it's too dark to read. 5
Next to a dog a book is man's best friend. 6
Inside a dog it's too dark to read. 6
Next to a dog a book is man's best friend. 7
Inside a dog it's too dark to read. 7
Next to a dog a book is man's best friend. 8
Inside a dog it's too dark to read. 8
Next to a dog a book is man's best friend. 9
Inside a dog it's too dark to read. 9



--
users mailing list
users at lists.fedoraproject.org
To unsubscribe or change subscription options:
https://admin.fedoraproject.org/mailman/listinfo/users
Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
Have a question? Ask away: http://ask.fedoraproject.org

Search Discussions

  • Ali Corbin at Mar 28, 2012 at 12:21 pm
    I solved a similar problem by installing gnu parallel on my system.
    It did everything that I wanted, and better than I would have coded.
    Ali
    On Tue, Mar 27, 2012 at 6:37 PM, Mark LaPierre wrote:

    Check out the redirection at the end of each command. 1>&2 redirects
    the standard out of your child command to the standard error which then
    appears in the parent shell. At the end the last & launches your
    command into a background shell and then moves on to launch the next
    command. The redirections don't care if the command ever terminates.

    The result is that both commands are launched and the parent shell
    terminates leaving the standard error attached to the terminal that the
    parent was launched in.
    On 03/27/2012 09:08 PM, bruce wrote:
    marklapier at aol.com

    hey mark....

    what you have, appears to be pretty close to what i had... except my
    tests never ended... the loops are infinite...

    can i do a fpaste and have you take a look at what i have?

    -btuce


    On Tue, Mar 27, 2012 at 9:00 PM, Mark LaPierrewrote:
    On 03/27/2012 05:25 PM, bruce wrote:

    hi.

    got a couple of test bash scripts.

    dog.sh, cat.sh
    each script runs the underlying php in an endless loop.

    I'm trying to figure out how to run the scripts in parallel, from the
    same parent shell script. something like:

    test.sh


    where dog.sh would be :
    --------------------------------
    while true
    do
    pgrep dog
    if [ $? -ne 0 ]
    then
    /dog.php
    fi
    sleep 5
    done

    my current tests, run dog.sh, which runs the dog.php ... but the test
    never gets to run cat.sh

    thoughts/comments...

    thanks
    Hey Bruce,

    Do you mean to run these subprograms in parallel or in series?

    cat.sh
    #! /bin/bash

    CAT=0
    until [ $CAT -eq 10 ]
    do
    echo "Inside a dog it's too dark to read. $CAT"
    CAT=$[$CAT + 1]
    sleep 2
    done


    dog.sh
    #! /bin/bash

    DOG=0
    until [ $DOG -eq 10 ]
    do
    echo "Next to a dog a book is man's best friend. $DOG"
    DOG=$[$DOG + 1]
    sleep 2
    done


    test.sh
    #! /bin/sh

    /home/mlapier/test/dog.sh 1>&2&
    /home/mlapier/test/cat.sh 1>&2&


    [mlapier at mushroom test]$ ./test.sh
    [mlapier at mushroom test]$ Next to a dog a book is man's best friend. 0
    Inside a dog it's too dark to read. 0
    Next to a dog a book is man's best friend. 1
    Inside a dog it's too dark to read. 1
    Next to a dog a book is man's best friend. 2
    Inside a dog it's too dark to read. 2
    Next to a dog a book is man's best friend. 3
    Inside a dog it's too dark to read. 3
    Next to a dog a book is man's best friend. 4
    Inside a dog it's too dark to read. 4
    Next to a dog a book is man's best friend. 5
    Inside a dog it's too dark to read. 5
    Next to a dog a book is man's best friend. 6
    Inside a dog it's too dark to read. 6
    Next to a dog a book is man's best friend. 7
    Inside a dog it's too dark to read. 7
    Next to a dog a book is man's best friend. 8
    Inside a dog it's too dark to read. 8
    Next to a dog a book is man's best friend. 9
    Inside a dog it's too dark to read. 9



    --
    users mailing list
    users at lists.fedoraproject.org
    To unsubscribe or change subscription options:
    https://admin.fedoraproject.org/mailman/listinfo/users
    Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
    Have a question? Ask away: http://ask.fedoraproject.org
    _______________________________________________
    CentOS mailing list
    CentOS at centos.org
    http://lists.centos.org/mailman/listinfo/centos

Related Discussions

Discussion Navigation
viewthread | post
Discussion Overview
groupcentos @
categoriescentos
postedMar 27, '12 at 9:37p
activeMar 28, '12 at 12:21p
posts2
users2
websitecentos.org
irc#centos

2 users in discussion

Ali Corbin: 1 post Mark LaPierre: 1 post

People

Translate

site design / logo © 2021 Grokbase