39

So I have a script that, when I give it two addresses, will search two HTML links:

echo "http://maps.google.be/maps?saddr\=$1\&daddr\=$2" | sed 's/ /%/g'

I want to send this to wget and then save the output in a file called temp.html. I tried this, but it doesn't work. Can someone explain why and/or give me a solution please?

#!/bin/bash
url = echo "http://maps.google.be/maps?saddr\=$1\&daddr\=$2" |  sed 's/ /%/g'
wget $url
  • For debugging something like this checking your variable values (by echo-ing them to the terminal) often gets you to the solution quickly. – kasterma Dec 13 '10 at 13:52
38

You can use backticks (`) to evaluate a command and substitute in the command's output, like:

echo "Number of files in this directory: `ls | wc -l`"

In your case:

wget `echo http://maps.google.be/maps?saddr\=$1\&daddr\=$2 | sed 's/ /%/g'`
16

You could use "xargs". A trivial example:

ls -1 *.c | sort -n | xargs cat

You would have to take care that xargs doesn't split its stdin into two or more invocations of the comman ("cat" in the example above).

  • I ended up here, because I couldn't remember this command name. My favorite use case was indeed: xargs -I % some_command --input=% -e -t -c (I put it here as a note for others that follow the same trace) – mpasko256 Dec 12 '17 at 21:22
13

you're not actually executing your url line :

#!/bin/sh
url="$(echo http://maps.google.be/maps?saddr\=$1\&daddr\=$2 | sed 's/ /%/g')"
wget $url
4

It seems you could use a combination of the answers here. I'm guessing you are wanting to replace space chars with their escaped ascii values in the url. To do this, you need to replace them with "%20", not just "%". Here's a solution that should give you a complete answer:

$ wget `echo http://maps.google.be/maps\?saddr\=$1\&daddr\=$2 | sed -e 's/\ /\%20/g'` -q -O temp.html

The backticks indicate that the enclosed command should be interpreted first, and the result sent to wget. Notice I escaped the space and % chars in the sed command to prevent them from being misinterpreted. The -q option for wget prevents processing output from the command being printed to the screen (handy for scripting when you don't care about the in-work status) and the -O option specifies the output file. FYI, if you don't want to save the output to a file, but just view it in the terminal, use "-" instead of a filename to indicate stdout.

3

wget also accepts stdin with the - switch.

If you want to save the output in a file, use the -O switch.

echo http://maps.google.be/maps?saddr\=$1\&daddr\=$2 | sed 's/ /%/g' | wget -i- -O temp.html

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