How to do a while loop with a string redirected into it
Im trying to loop though a string with开发者_运维知识库 HTTP links inside and newlines, I want to loop over a line at a time.
At the moment I have
echo -e "$HTTP_LINKS" | while read HTTP_S_LINK ; do
TEST_STRING="test"
done
But this way I don't have access to the TEST_STRING out side the loop, which is what I want. I'm using the while loop so that it will loop though each newline in $HTTP_LINKS and not just the words in the string. (I don't want to use a for loop with IFS set to \n)
I thought maybe I could just do something like this
#!/bin/bash
while read HTTP_S_LINKS
do
TEST_STRING="test2"
done < $HTTP_LINKS
But of course this doesn't work as $HTTP_LINKS contains a string and not a link to a file.
You had the right idea with your 2nd snipit but you need to use 'Here Strings' via the <<<
syntax. You cant access $TEST_STRING
outside of your first snipit because the pipe creates a sub-shell; using the here-string does not. Also, make sure you quote "$HTTP_LINKS"
otherwise you'll lose the newlines.
#!/bin/bash
HTTP_LINKS=$(echo -e "http://www.aaa.com\nhttp://www.bbb.com")
unset TEST_STRING;
while read url;
do
((TEST_STRING++))
done <<<"$HTTP_LINKS"
echo $TEST_STRING
Output
2
If you initialize and export the TEST_STRING variable outside the loop you should have access to it after the loop.
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