MATLAB: Opening two files within a function

Question

hello! i need to open two files within a function, but it doesn't work. i can open one file – no problem, but when i try to open an other it says:

??? Error using ==> fgetl at 44 Invalid file identifier. Use fopen to generate a valid file identifier.

Error in ==> fileopentest at 18 zahl = str2num(fgetl(fid2));

i've tried to close the first file, i've tried to use the full path of the second file, its allways the same message i get. can anybody please help?

Answer 1

Use the two-output form of fopen:

[fid2, message2] = fopen(....);
if fid2 < 0
  disp(['open #2 failed because: ', message2])
end