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Getting Rid of Having to Write to Flat Files


 
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# 1  
Old 07-28-2009
Getting Rid of Having to Write to Flat Files

Ok,

so i've been having to write to flat files lately and then making my script read information from the flat file and then work off of that.

i dont want to keep doing that because i believe it creates a mess. i like to keep my work all to one script instead of having that one script create temp files.

so, is there there a way to write the informationn that would have been written to a flat file to the memory and work off the memory as if it were a flat file?
# 2  
Old 07-28-2009
you can use variables???
# 3  
Old 07-28-2009
Quote:
Originally Posted by ahmedwaseem2000
you can use variables???


how do you make the variable recognizable or retrievable or accessible throughout the script? can you give an example?
# 4  
Old 07-28-2009
assign the value to a variable and you can retreive by adding '$' at the begining of the variable name like the example below. incase, if you want to make it accessible from different processes then you can export the variable like the 2nd example.

Code:
Example 1: Variable=XXXXX
echo $Variable
Example 2:export Variable=XXXXX
echo $Variable

# 5  
Old 07-28-2009
Quote:
Originally Posted by ahmedwaseem2000
assign the value to a variable and you can retreive by adding '$' at the begining of the variable name like the example below. incase, if you want to make it accessible from different processes then you can export the variable like the 2nd example.

Code:
Example 1: Variable=XXXXX
echo $Variable
Example 2:export Variable=XXXXX
echo $Variable

Perfect. thanks. the second example is what I think i needed.

---------- Post updated at 12:01 PM ---------- Previous update was at 11:40 AM ----------

Quote:
Originally Posted by ahmedwaseem2000
assign the value to a variable and you can retreive by adding '$' at the begining of the variable name like the example below. incase, if you want to make it accessible from different processes then you can export the variable like the 2nd example.

Code:
Example 1: Variable=XXXXX
echo $Variable
Example 2:export Variable=XXXXX
echo $Variable


what happens if I wanted to add to the contents of the $Variable, like i would be able to do if i were to write to a flat file? is that possible?
# 6  
Old 07-28-2009
Code:
variable=XXXXX
echo $variable
XXXXX
variable="$variable YYYYY"
echo $variable
XXXXX YYYYY

# 7  
Old 07-28-2009
Only comment is about passing variables to children processes. you can pass them as arguments on the command line or use:
Code:
export variable

the child process will pick it up.
You need to keep in mind some limitations of variables.
Particularly things like:
Code:
var1='<file1'

this variable will store it, but when using it in a straight forward way it will not work.
Code:
sed $var1

does not do what is expected

to make it work on eneds to use eval command

Code:
eval sed $var1

will work as expected

Last edited by gch; 07-28-2009 at 05:53 PM..

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