colobot-data/help/cbot/E/open.txt

\b;Instruction \c;open\n;
Open a text file in the files/ folder. This is a method of the \c;\l;file\u cbot\file;\n; class. This is the reason why we always write \c;handle.open()\n;:
\c;
\s;	handle.open("test.txt", "w");
\n;
To open a file, proceed as follows:
\c;
\s;	file handle();
\s;	handle.open("filename", "w");
\s;	handle.writeln("abc");
\s;	handle.close();
\n;
\c;"r"\n; mode: open for reading.
\c;"w"\n; mode: open for writing.
\c;"a"\n; mode: open for appending.

Files can only be created and opened in the files/ folder which is located in the folder inside Colobot save directory. You cannot not create or open files that are located elsewhere than in the files/ folder.

\t;See also
\c;\l;file\u cbot\file;\n;, \c;\l;close\u cbot\close;\n;, \c;\l;readln\u cbot\readln;\n;, \c;\l;writeln\u cbot\writeln;\n; and \c;\l;eof\u cbot\eof;\n;.
\l;Programming\u cbot;, \l;types\u cbot\type; and \l;categories\u cbot\category;.