Very Computer

I don't understand why the for command in the pdksh-5.2.3 utility
doesn't act the same as the standard ksh shell.

This simple shell script:

#!/bin/ksh -x

cd /usr/adm
for cn in "messages debug secure lastlog wtmp utmp maillog POPlog
xferlog spoolerr";
do
    echo $cn;
    ls -l /usr/adm/${cn};
    cp $cn "$cn.`date "+%y%m%d"`";
done

Produces this output:

+ cd /usr/adm
+ echo messages debug secure lastlog wtmp utmp maillog POPlog xferlog
spoolerr
messages debug secure lastlog wtmp utmp maillog POPlog xferlog
spoolerr
+ ls -l /usr/adm/messages debug secure lastlog wtmp utmp maillog
POPlog xferlog spoo
lerr
-rw-rw-r--   1 root     root      3623724 May  5 22:32
/usr/adm/messages
-rw-r--r--   1 root     root      1019386 May  4 13:15 POPlog
-rw-r-----   1 root     root      8154400 May  5 22:30 debug
-rw-r--r--   1 root     root        14496 May  5 21:38 lastlog
-rw-r--r--   1 root     root        25197 May  5 13:10 maillog
-rw-r--r--   1 root     root        44082 May  5 21:38 secure
-rw-r--r--   1 root     root        19216 Apr 24 00:43 spoolerr
-rw-r--r--   1 root     root         5432 May  5 21:38 utmp
-rw-r--r--   1 root     root       355768 May  5 21:38 wtmp
-rw-r-----   1 root     root        34986 May  4 16:11 xferlog
+ date +%y%m%d
+ cp messages debug secure lastlog wtmp utmp maillog POPlog xferlog
spoolerr message
s debug secure lastlog wtmp utmp maillog POPlog xferlog
spoolerr.960505
cp: when copying multiple files, last argument must be a directory
Try `cp --help' for more information.

I don't understand why the script scans through all of the variables
before executing each of the commands.  What did I do wrong here?

This script is intended to copy various files to a similar filename
with a date extension which I then intend on compressing and keeping
for 3 months.  Unfortunately this script presents all of the variables
to each command in succession before it executes each command.

Any advice?

Quote:>I don't understand why the for command in the pdksh-5.2.3 utility
>doesn't act the same as the standard ksh shell.

>#!/bin/ksh -x

>cd /usr/adm
>for cn in "messages debug secure lastlog wtmp utmp maillog POPlog
>xferlog spoolerr";
>do
>    echo $cn;
>    ls -l /usr/adm/${cn};
>    cp $cn "$cn.`date "+%y%m%d"`";
>done

>I don't understand why the script scans through all of the variables
>before executing each of the commands.  What did I do wrong here?

That should do it for you - the double quotes escape the spaces in
your example and turn all the args into 1.

HTH

-Larry

--
  Larry Daffner        |  Linux: Unleash the workstation in your PC!

Never underestimate the bandwidth of a station wagon full of mag tapes
        -- Dennis Ritchie

Quote:>I don't understand why the for command in the pdksh-5.2.3 utility
>doesn't act the same as the standard ksh shell.
>This simple shell script:
>for cn in "messages debug secure lastlog wtmp utmp maillog POPlog
           ^
>xferlog spoolerr";

[snip]

Quote:>I don't understand why the script scans through all of the variables
>before executing each of the commands.  What did I do wrong here?

$ for a in "a b c"

Quote:> do
> echo $a
> done

a b c

indicating that the loop was only executed once. If you remove the quotes,
you get

a
b
c

which is probably what you intended. pdksh has compatibility problems, but
this is not one of them.

Success with your script, Joris

------------If debugging is the art of removing bugs, then programming must
Joris S. Zwart           be the art of putting them in - Edsger W. Dijkstra

(PGP public key available by finger)----------------#include <disclaimer.h>