Re: shell script problem
In freebsd-questions Digest, Vol 447, Issue 1, Message: 13 On Sun, 23 Dec 2012 18:48:12 +0100 Dh?nin Jean-Jacques > 2012/12/23 Polytropon > > #!/bin/sh > > > > cat foo.txt | while read LINE1 > > do > > cat bar.txt | while read LINE2 > > do > > if [ "$LINE1" = "$LINE2" ]; then > > sw="1" > > echo "Current value of sw is : " $sw > > > * ps -l | grep $$ * > # see subshell here Yes indeed. > > break > > fi > > done > > > > * echo " Process: " $$* > # And the parent Yep. > > echo "Value of sw is : " $sw > > if [ "$sw" = "0" ]; then > > echo "DO SOMETHING!" > > fi > > sw="0" > > done > > > > I suggest : > > -%><- > > #!/bin/sh > > cat foo.txt | while read LINE1 > do > echo 'One' > $$tmp > cat bar.txt |while read LINE2 > do > if [ "$LINE1" = "$LINE2" ]; then > echo 'ok' > $$tmp > break > fi > done > > if [ `cat $$tmp` = "One" ]; then > echo "One !" > fi > > if [ `cat $$tmp` = "ok" ]; then > echo "ok !" > fi > done Or, to avoid subshell(s) created in pipeline(s), and subsequent loss of variables set in the subshell(s) to their parents, rather than using: cat foo.txt | while read LINE1 [..] cat bar.txt | while read LINE2 [..] done [..] done you can use: while read LINE1 [..] while read LINE2 [..] done < bar.txt [..] done < foo.txt cheers, Ian ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: shell script problem
2012/12/23 Polytropon > > #!/bin/sh > > cat foo.txt | while read LINE1 > do > cat bar.txt | while read LINE2 > do > if [ "$LINE1" = "$LINE2" ]; then > sw="1" > echo "Current value of sw is : " $sw > * ps -l | grep $$ * # see subshell here > break > fi > done > * echo " Process: " $$* # And the parent > echo "Value of sw is : " $sw > if [ "$sw" = "0" ]; then > echo "DO SOMETHING!" > fi > sw="0" > done > I suggest : -%><- #!/bin/sh cat foo.txt | while read LINE1 do echo 'One' > $$tmp cat bar.txt |while read LINE2 do if [ "$LINE1" = "$LINE2" ]; then echo 'ok' > $$tmp break fi done if [ `cat $$tmp` = "One" ]; then echo "One !" fi if [ `cat $$tmp` = "ok" ]; then echo "ok !" fi done Best regards - (°> Dhénin Jean-Jacques / ) 48, rue de la Justice 78300 Poissy ^^ dhe...@gmail.com - ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: shell script problem
2012/12/23 Polytropon > On Sun, 23 Dec 2012 10:34:34 +0100, Polytropon wrote: > > First, the lines with "read" have to be: > > > > cat /foo/bar.txt | while read $LINE1 > > > > cat /foo/bar/foo/bar.txt | while read $LINE2 > > > > Reason: $LINE1 and $LINE2 will be evaluated here, they are "empty > > string", causing "read" to throw an error. > > Excuse me - I made a mistake! Of course those two lines > have to be: > > cat /foo/bar.txt | while read LINE1 > > and > > cat /foo/bar/foo/bar.txt | while read LINE2 > > The $ infront of the variable names have to be removed. > The variable _name_, not its content, has to be provided > to "read" as a parameter. > > The script so far: > > > > #!/bin/sh > > cat foo.txt | while read LINE1 > * echo "Pid Process: " $$* > do > cat bar.txt | while read LINE2 > do > if [ "$LINE1" = "$LINE2" ]; then > sw="1" > echo "Current value of sw is : " $sw > *ps -ax |grep bar * > break > fi > done > echo "Value of sw is : " $sw > if [ "$sw" = "0" ]; then > echo "DO SOMETHING!" > fi > sw="0" > done > Has you can see, "pipe" make a subshell and sw is lost. Hope this help - (°> Dhénin Jean-Jacques / ) 48, rue de la Justice 78300 Poissy ^^ dhe...@gmail.com - ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: shell script problem
On Sun, 23 Dec 2012 09:57:02 + Matthew Seaman wrote: > Hmmm I'd just like to draw your attention to the comm(1) program, > which lets you find lines common to two files, or only in one or other > of a pair of inputs, very easily. The only slight gotcha is that the > input files have to be sorted. For which purpose the sort program is most useful. -- Steve O'Hara-Smith ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: shell script problem
On 23/12/2012 09:43, Polytropon wrote: > On Sun, 23 Dec 2012 10:34:34 +0100, Polytropon wrote: >> First, the lines with "read" have to be: >> >> cat /foo/bar.txt | while read $LINE1 >> >> cat /foo/bar/foo/bar.txt | while read $LINE2 >> >> Reason: $LINE1 and $LINE2 will be evaluated here, they are "empty >> string", causing "read" to throw an error. > > Excuse me - I made a mistake! Of course those two lines > have to be: > > cat /foo/bar.txt | while read LINE1 > > and > > cat /foo/bar/foo/bar.txt | while read LINE2 > > The $ infront of the variable names have to be removed. > The variable _name_, not its content, has to be provided > to "read" as a parameter. > > The script so far: > > > > #!/bin/sh > > cat foo.txt | while read LINE1 > do > cat bar.txt | while read LINE2 > do > if [ "$LINE1" = "$LINE2" ]; then > sw="1" > echo "Current value of sw is : " $sw > break > fi > done > echo "Value of sw is : " $sw > if [ "$sw" = "0" ]; then > echo "DO SOMETHING!" > fi > sw="0" > done > > Hmmm I'd just like to draw your attention to the comm(1) program, which lets you find lines common to two files, or only in one or other of a pair of inputs, very easily. The only slight gotcha is that the input files have to be sorted. Cheers, Matthew -- Dr Matthew J Seaman MA, D.Phil. PGP: http://www.infracaninophile.co.uk/pgpkey signature.asc Description: OpenPGP digital signature
Re: shell script problem
On Sun, 23 Dec 2012 10:34:34 +0100, Polytropon wrote: > First, the lines with "read" have to be: > > cat /foo/bar.txt | while read $LINE1 > > cat /foo/bar/foo/bar.txt | while read $LINE2 > > Reason: $LINE1 and $LINE2 will be evaluated here, they are "empty > string", causing "read" to throw an error. Excuse me - I made a mistake! Of course those two lines have to be: cat /foo/bar.txt | while read LINE1 and cat /foo/bar/foo/bar.txt | while read LINE2 The $ infront of the variable names have to be removed. The variable _name_, not its content, has to be provided to "read" as a parameter. The script so far: #!/bin/sh cat foo.txt | while read LINE1 do cat bar.txt | while read LINE2 do if [ "$LINE1" = "$LINE2" ]; then sw="1" echo "Current value of sw is : " $sw break fi done echo "Value of sw is : " $sw if [ "$sw" = "0" ]; then echo "DO SOMETHING!" fi sw="0" done -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
Re: shell script problem
On Sun, 23 Dec 2012 01:05:35 -0800 (PST), Jack Mc Lauren wrote: > Hi all > Please take a look at the script below wich I've wrote : > 1- cat /foo/bar.txt | while read $LINE12- do3- cat /foo/bar/foo/bar.txt | > while read $LINE24- do 5- if [ "$LINE1" = "$LINE2" ]; then6- > sw="1"7- echo "Current value of sw is : " $sw8- > break9- fi10- done11- echo "Value of sw is : " $sw12- > if [ "$sw" = "0" ]; then13- DO SOMETHING14- fi15- sw="0"16- > done This is totally distorted! Allow me to re-arrange it. cat /foo/bar.txt | while read $LINE1 do cat /foo/bar/foo/bar.txt | while read $LINE2 do if [ "$LINE1" = "$LINE2" ]; then sw="1" echo "Current value of sw is : " $sw break fi done echo "Value of sw is : " $sw if [ "$sw" = "0" ]; then DO SOMETHING fi sw="0" done First, the lines with "read" have to be: cat /foo/bar.txt | while read $LINE1 cat /foo/bar/foo/bar.txt | while read $LINE2 Reason: $LINE1 and $LINE2 will be evaluated here, they are "empty string", causing "read" to throw an error. > You probebly guessed what I want to do. But the problem is that > when the value of sw sets to 1 (in the first if statement) and > the loop breaks , the value of sw is not '1' anymore in > " echo "Value of sw is : " $sw " !!! > Thanks in advance ... For testing, I've replaced the $sw=0 line with an "echo" command. I've created two files foo.txt and bar.txt for test, both have one line in common (3rd line in my example data). If I run the script, I get this output: Value of sw is :<- after 1st line (uninitialized) Value of sw is : 0 <- after 2nd line DO SOMETHING! Current value of sw is : 1 <- after 3nd line (common entry) Value of sw is : 0 <- after 4th line DO SOMETHING! Value of sw is : 0 <- after 5th line DO SOMETHING! It seems that the condition $LINE1=$LINE2 properly triggers the "current value" echo command, while all non-common lines trigger the "DO SOMETHING" action. If you indended something else, please elaborate. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ... ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
