sub and gsub function?

Question

I have this command:

$ find $PWD -name "*.jpg" | awk '{system( "echo "  $(sub(/\//, "_")) ) }'
_home/mol/Pulpit/test/1.jpg

Now the same thing, but using gsub:

$ find $PWD -name "*.jpg" | awk '{system( "echo "  $(gsub(/\//, "_")) ) }'

mol@mol:~

I want to get the result:

_home_mol_Pulpit_test_1.jpg

Thank you for your help.

EDIT:

I put 'echo' to test the command:

$ find $PWD -name "*.jpg" | awk '{gsub("/", "_")} {system( "echo " mv $0 " " $0) }'
_home_mol_Pulpit_test_1.jpg _home_pic_Pulpit_test_1.jpg

mol@mol:~

I want to get the result:

$ find $PWD -name "*.jpg" | awk '{gsub("/", "_")} {system( "echo " mv $0 " " $0) }'
/home/pic/Pulpit/test/1.jpg  _home_pic_Pulpit_test_1.jpg

Answer 1

That won't work if the string contains more than one match... try this:

echo "/x/y/z/x" | awk '{ gsub("/", "_") ; system( "echo "  $0) }'

or better (if the echo isn't a placeholder for something else):

echo "/x/y/z/x" | awk '{ gsub("/", "_") ; print $0 }'

In your case you want to make a copy of the value before changing it:

echo "/x/y/z/x" | awk '{ c=$0; gsub("/", "_", c) ; system( "echo " $0 " " c )}'