Version Control with Subversion

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Appendix A: Subversion for CVS Users

Second, Subversion maintains an internal notion of whether a file is text or binary

data, but this notion is only extant in the working copy. During an

svn update, Sub-

version will perform contextual merges on locally modified text files, but will not

attempt to do so for binary files.

To determine whether a contextual merge is possible, Subversion examines the

svn:

mime-type

property. If the file has no svn:mime-type property, or has a mime-type that

is textual (e.g. text/*), Subversion assumes it is text. Otherwise, Subversion assumes

the file is binary. Subversion also helps users by running a binary-detection algo-

rithm in the

svn import and svn add commands. These commands will make a good

guess and then (possibly) set a binary svn:mime-type property on the file being

added. (If Subversion guesses wrong, the user can always remove or hand-edit the

property.)

Versioned Modules

Unlike CVS, a Subversion working copy is aware that it has checked out a module.

That means that if somebody changes the definition of a module, then a call to

svn

update

will update the working copy appropriately.

Subversion defines modules as a list of directories within a directory property: see

“Externals Definitions” in Chapter 7.

Authentication

With CVS’s pserver, you ...