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Files that are not in binary mode have CR LF sequences translated to LF on input and LF translated to CR LF on output. Binmode has no effect under Unix; in MS-DOS and similarly archaic systems, it may be imperative--otherwise your MS-DOS-damaged C library may mangle your file. The key distinction between systems that need <code>binmode()</code> and those that don't is their text file formats. Systems like Unix, MacOS, and Plan9 that delimit lines with a single character, and that encode that character in C as <code>"\n"</code>, do not need <code>binmode()</code>. The rest need it. If FILEHANDLE is an expression, the value is taken as the name of the filehandle.</p> </dd> </dl> </div> <div id="footer"> <p>Perldoc Browser is maintained by Dan Book (<a href="https://metacpan.org/author/DBOOK">DBOOK</a>). 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