Question

How would I go about checking whether gcc has succeeded in compiling a program, failed, or succeeded but with a warning?

#!/bin/sh

string=$(gcc helloworld.c -o helloworld)

if [ string -n ]; then
    echo "Failure"
else
    echo "Success!"
fi

This only checks whether it has succeeded or (failed or compiled with warnings).

-n means “is not null”.

Thanks!

EDIT If it’s not clear, this isn’t working.

Answer 1

if gcc helloworld.c -o helloworld; then 
echo "Success!";
else 
echo "Failure"; 
fi

You want bash to test the return code, not the output. Your code captures stdout, but ignores the value returned by GCC (ie the value returned by main()).