Define a string in qmake command line

Question

I need to pass a string as a definition to my source code which is a base64 encoded string (so may contain / and "). I'm using qmake and g++. I've tried so many combinations, but neither works:

qmake DEFINES+=SERIAL=\\\"f9a/z\\\"
qmake DEFINES+=SERIAL=\"f9a/z\"
qmake DEFINES+="SERIAL=\\"f9a/z\\\""

G++ should get the serial like this:

g++ -DSERIAL=\"f9a/z\"

Answer 1

In bash:

qmake DEFINES+=SERIAL=\\\\\\\"\"f9a/z\\\\\\\"\"

In a scripting language:

"DEFINES+=SERIAL=\\\\\\\"" + str + "\\\\\\\""