How can I add one character before each line of textfile?

How can I add one character before each line of textfile and output a new textfile with the changes made?

Answer 1

[Konstantinos Sofos]

Hi Bob,

What about this:

   fid1 = fopen('file1.txt');
   fid2 = fopen('file2.txt','w');
   tline = fgets(fid1);
   Character2add = 'xx_'; % here put the character to be added
   while ischar(tline)
      disp(tline)
      fprintf(fid2,'%s %s\n',Character2add,tline);
      tline = fgets(fid1);
   end

   fclose(fid1);
   fclose(fid2);

Regards