Directing cat or grep command in variable

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# 1  
Old 03-11-2013
Directing cat or grep command in variable


I still have the problem with directing information from cat or grep to a variable.

For instance:
XMSG "$(date +%Y_%m_%d)_error_report.txt" "$(cat "$(date +%Y_%m_%d)_error_report.txt")" &

Works! The text received by cat is directed to my function.

If it is written like this, my variable var is empty
var=$(cat "$(date +%Y_%m_%d)_error_report.txt")

Same effect here:
var=$(grep "sdhdjhf" text.txt)

Can anybody please explain why the redirection does not work?
# 2  
Old 03-11-2013
I would doubt on the multiple lines that cat file and grep something file would return Smilie

Or non-existence of the file in case of cat and nothing found in case of grep
# 3  
Old 03-11-2013
It oughta work. Seems to work here with this test scenario. Similar to previous response, two likely causes would be "file is empty" or "grep didn't find anything".

echo "Line 1"  > lines.x
echo "Line 2" >> lines.x
x=`cat lines.x`
echo x = $x
y=$(cat lines.x)
echo y = $y
rm lines.x

x = Line 1 Line 2
y = Line 1 Line 2

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