Text and Binary Files

Linefeeds

On the Macintosh, a carriage return character is normally used to indicate the end of a line (or, in word processors, the end of a paragraph). This is not the case on other computers. On IBMs and compatibles, a carriage return is always followed by a linefeed, and on Unix systems, a sole linefeed is used. ZipIt will convert text files using either of these two formats to Macintosh format automatically, during decompression. ZipIt will usually be able to detect when this must be done. However, if you would like to manually toggle this feature, simply select the files and choose “Add/Strip Linefeeds” from the Zip menu.

ZipIt will also add linefeeds to text files destined for non-Macintosh systems. You must tell ZipIt to add linefeeds before the file is zipped; ZipIt cannot add linefeeds to a file once it is already saved. You can turn this option on by clicking in the linefeed square (the square in the “LF” column) in the zip window next to the file to which you want to add linefeeds, or by selecting that file and choosing “Add/Strip Linefeeds” from the Zip menu. If the square is filled in, linefeeds will be added when the file is saved. By default, linefeeds will be added to all text files if the Preference for adding and stripping linefeeds is set.

Important: Suppose you create an archive. Your IBM friend successfully unzips it, but cannot use the files inside. The first thing you should try is to toggle the setting of the “Add/Strip Linefeeds” menu command (or the LF button). Similarly, if you have a zip archive that contains files that you can successfully unzip, but cannot use, change this setting.

Distinguishing Between Text and Binary Files

In order to determine whether or not to strip linefeeds from a file, ZipIt normally examines the information left by the program that originally created the archive. If that program marked a specific file as text, then ZipIt will strip linefeeds; otherwise, it will not. However, such programs often make mistakes. If you find that you receive many files with a certain extension, say, FILE.DOC, and that those files are invariably text files, even though they are not marked as such, then you may override the demarkation and allow ZipIt to recognize these files as text. (You may also force ZipIt to recognize these files as binary.) Add the files to the Extension mapping preference dialog box, and either set or leave unset the “Text File” checkbox. See the “Extension mapping” subsection of the “Preferences” chapter, below.