AIX

Hi,

I have the current script with the following code and it works ok.

Code:

for i in `find . -name "???ABCEDFGH*"`
do
    SESS_NO=`echo $i | awk -F "." '{print $3}'`
    rm -f $LOGDIR/${OT_QUEUEID}*${SESS_NO}.log 2>/dev/null
    rm -f $i 2>/dev/null
done

I want to remove the usage of the following code and replace it with something else since there could be limits as to the size of arguments that a "for" command could take in AIX 5.2 ksh where in this executes.

Code:

`find . -name "???ABCEDFGH*"`

I could convert the same into something as follows

Code:

> /tmp/abcdefgh.txt
find . -name "???ABCDEFGH*" > /abcdefgh.txt
while read line
do
     SESS_NO=`echo $line | awk -F "." '{print $3}'`
     rm -f $LOGDIR/${OT_QUEUEID}*${SESS_NO}.log 2>/dev/null
     rm -f $line 2>/dev/null
done < /tmp/abcdefgh.txt

Please advise me on more alternate efficient methods other than what I have provided above.
Thx
Jerardfjay

Welcome as the first member of the i-shun-for-loops-for-their-inherent-danger-club. The drinks are on the clubs president - me. ;-)

You are absolutely correct and i have said it a dozen times here that for-loops on unlimited content (like a directory listing) are a dangerous thing, because the code could break as the maximum command line length is reached.

You can run it directly in a pipeline without the intermediate file:

Code:

find /path/to/dir -name "something" -print | while read filename ; do
     do_something $filename
done

Btw., speaking of coding practice: maybe its only me but i find it easier to read later when the input to the while-loop is at the top and not the bottom. Therefore this:

Code:

cat file | while read line ; do
     do_something $line
done

is easier to read than that, especially when the loop is long:

Code:

while read line ; do
     do_something $line
done < file

I hope this helps.

bakunin

There is also the "xargs" command which takes long inputs and creates a command for each line.

E.g. find some files and run the "file" (appears after xargs) on each one of them:

# find /usr/lib -name '*.so' | xargs file
/usr/lib/kdb/auto/GetLine/GetLine.so: executable (RISC System/6000) or object module not stripped
/usr/lib/IbTsLib/libTsIb.so: executable (RISC System/6000) or object module not stripped
/usr/lib/IbGxLib/libGxIb.so: executable (RISC System/6000) or object module not stripped
[snip]