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Use file as list in for loop...

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# 8  
Old 06-14-2007
Quote:
Originally Posted by earnstaf
Can I use a file as the list in a for loop? I tried it like this:

Code:
workstation=( $(cat /home/me/file) )
for ws in $workstation

Code:




Code:



workstation=$(cat /home/me/file)
for ws in $workstation






Or:




Code:



for ws in "${workstation[@]}"






Those will work with the example file you gave, but it is almost always the wrong way to read a file.






Quote:



    
    
do
command
done

Quote:

The contents of file are like:

abc
def
ghi

It only read the initial line.

Does each item have to be quoted? Do they have to all be on the same line? ...or is it not possible at all?

Thanks for your help.

The usual way to process a file in a script is:

Code:
while IFS= read -r line
do
   command
done < /home/me/file

# 9  
Old 06-14-2007
Quote:
Originally Posted by porter
according to the specification of what the input file looks like, this is what was requested.
what WAS requested was 'a solution' which you did provide, but what I am saying there's no need for a 'cat' here and 'cat' here is UUOC here.
# 10  
Old 06-17-2007
hey u can do like this
workstation=`cat /home/me/file`
for ws in $workstation
do
command
done
# 11  
Old 06-18-2007
When thinking about a solution to read a file, size is for sure
the main consideration.
The solution of placing the entire file into a single variable
is definitely a bad solution for large files.
# 12  
Old 06-18-2007
Quote:
Originally Posted by Shell_Life
When thinking about a solution to read a file, size is for sure
the main consideration.
The solution of placing the entire file into a single variable
is definitely a bad solution for large files.
Understood.. thanks for clearing that up.
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