what is this mean?

sed 's/^ *//;s/ *$//'

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This removes empty lines as well as lines containing only spaces.
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This removes empty lines as well as lines containing only spaces.

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Thanks <br />
<br />
<br />
$SCAN_PASS=10<br />
$SCAN_TOTAL=20<br />
<br />
can you please advise what is this line does. do we need bc -l?<br />
<br />
$SCAN_PASS/$SCAN_TOTAL*100<wbr /> | bc -l | awk -F. '{print $1}'| sed 's/^ *//;s/ *$//'
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Thanks


$SCAN_PASS=10
$SCAN_TOTAL=20

can you please advise what is this line does. do we need bc -l?

$SCAN_PASS/$SCAN_TOTAL*100 | bc -l | awk -F. '{print $1}'| sed 's/^ *//;s/ *$//'

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sorry.<br />
<br />
SCAN_PASS=10<br />
SCAN_TOTAL=20<br />
<br />
not <br />
<br />
$SCAN_PASS=10<br />
$SCAN_TOTAL=20
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sorry.

SCAN_PASS=10
SCAN_TOTAL=20

not

$SCAN_PASS=10
$SCAN_TOTAL=20

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<div class="content wysiwyg-content">
I am trying to understand these line. Can some one explain as i am new to scripting. <br />
<br />
<br />
egrep 'PASS|FAIL' $LOGFILE | wc -l | sed 's/^ *//;s/ *$//'<br />
<br />
grep PASS $LOGFILE | wc -l | sed 's/^ *//;s/ *$//'<br />
<br />
grep FAIL $LOGFILE | wc -l | sed 's/^ *//;s/ *$//'<br />
<br />
echo $SCAN_PASS/$SCAN_TOTAL*100<wbr /> | bc -l | awk -F. '{print $1}'| sed 's/^ *//;s/ *$//'
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</div>


I am trying to understand these line. Can some one explain as i am new to scripting. 


egrep 'PASS|FAIL' $LOGFILE | wc -l | sed 's/^ *//;s/ *$//'

grep PASS $LOGFILE | wc -l | sed 's/^ *//;s/ *$//'

grep FAIL $LOGFILE | wc -l | sed 's/^ *//;s/ *$//'

echo $SCAN_PASS/$SCAN_TOTAL*100 | bc -l | awk -F. '{print $1}'| sed 's/^ *//;s/ *$//'

sed - script

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