What does "wget -O" mean?

Question

I have an wget command like this in my shell script:

reponse="`wget -O- http:localhost:8080/app/index.html`" 

I don't understand the -O- option. I was explained that -O is output to somewhere and - is output to the current stream. I don't see any explaination of "-" in wget. Is that a standard thing for shell scripting. Where I can find reference to it?

Thanks,

Answer 1

Here's the man page of wget -O:

http://www.gnu.org/software/wget/manual/html_node/Download-Options.html#Download-Options

Here's a few examples:

1. wget with no flag

   wget www.stackoverflow.com 

   Output:

   A file named as index.html

2. wget with -O flag

   wget -O filename.html www.stackoverflow.com 

   Output:

   A file named as filename.html

3. wget with -O- flag

   wget -O- www.stackoverflow.com 

   Output:

   Output to stdout

Answer 2

for the manual of wget: use man wget if you are on Unix platform. Else, try "man page wget" on google.

The -O- stand for "Get as a file and print the result on STDOUT"