There is unfortunately no code generation support for the input function as of MATLAB R2019a. We've made an internal note of your request so we can look at lifting that limitation in the future.
In the interim, here is a potential workaround -
function y = foo
y = input_codegen('Enter a number: ');
fprintf('Read: %s\n',y);
end
function resp = input_codegen(prompt)
%#codegen
coder.extrinsic('input');
if coder.target('MEX') || coder.target('MATLAB') || coder.target('Sfun')
resp = input(prompt, 's');
else
coder.cinclude('<stdio.h>');
fprintf('%s',prompt);
cresp = char(zeros(1,1024));
coder.ceval('fgets',coder.ref(cresp(1)), 1023, coder.opaque('FILE*','stdin'));
% Call strlen in C and trim output
slen = int32(1);
slen = coder.ceval('strlen',coder.rref(cresp(1)));
resp = cresp(1:slen);
end
end
