Read text file line-by-line in deployed application

I am trying to read a large TXT file in my deployed application, but I am encountering memory limitations. Therefore, I would like to read in the TXT file line by line, but the function 'fgetl' is not supported for C/C++ code generation with MATLAB Coder. 

Is there any other way to read a TXT file line by line?

Answer 1

[MathWorks Support Team]

This can be achieved using the functions "fgets" or "fgetl". The code generation support for these functions was introduced in R2019b. To access the release-specific documentation for "fgets", execute the following command in the MATLAB R2019b command window:

>> web(fullfile(docroot, 'matlab/ref/fgets.html'))

For "fgetl", use the following command:

>> web(fullfile(docroot, 'matlab/ref/fgetl.html'))

For C/C++ deployment of your MATLAB code in releases prior to R2019b, you will have to write your own implementation of this functionality.

One possible solution to read a TXT file line-by-line could be as follows:

function main %#codegen fid = fopen('myfile.txt'); lne = myfgetl(fid); while ~isempty(lne) fprintf(1,'%s',lne); fprintf(1,'%s',sprintf('
')); lne = myfgetl(fid); end fclose(fid); end
function line = myfgetl(fid) line = ''; c = fread(fid,1,'char=>char'); while ~feof(fid) && ~strcmp(c, sprintf('
')) if ~strcmp(c,sprintf('\r')) line = [line,c]; end c = fread(fid,1,'char=>char'); end end

Please follow the link below to search for the required information regarding the current release:

https://www.mathworks.com/help/