Another way to examine your changes is with the svn diff command. You can find out exactly how you've modified things by running svn diff with no arguments, which prints out file changes in unified diff format:

$ svn diff
Index: bar.c
===================================================================
--- bar.c	(revision 3)
+++ bar.c	(working copy)
@@ -1,7 +1,12 @@
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <stdio.h>

 int main(void) {
-  printf("Sixty-four slices of American Cheese...\n");
+  printf("Sixty-five slices of American Cheese...\n");
 return 0;
 }

Index: README
===================================================================
--- README	(revision 3)
+++ README	(working copy)
@@ -193,3 +193,4 @@
+Note to self:  pick up laundry.

Index: stuff/fish.c
===================================================================
--- stuff/fish.c	(revision 1)
+++ stuff/fish.c	(working copy)
-Welcome to the file known as 'fish'.
-Information on fish will be here soon.

Index: stuff/things/bloo.h
===================================================================
--- stuff/things/bloo.h	(revision 8)
+++ stuff/things/bloo.h	(working copy)
+Here is a new file to describe
+things about bloo.

The svn diff command produces this output by comparing your working files against the cached “pristine” copies within the .svn area. Files scheduled for addition are displayed as all added-text, and files scheduled for deletion are displayed as all deleted text.

Output is displayed in unified diff format. That is, removed lines are prefaced with - and added lines are prefaced with +. svn diff also prints filename and offset information useful to the patch program, so you can generate “patches” by redirecting the diff output to a file:

$ svn diff > patchfile

You could, for example, email the patch file to another developer for review or testing prior to commit.

Subversion uses its internal diff engine, which produces unified diff format, by default. If you want diff output in a different format, specify an external diff program using --diff-cmd and pass any flags you'd like to it using the --extensions (-x) option. For example, to see local differences in file foo.c in context output format while ignoring case differences, you might run svn diff --diff-cmd /usr/bin/diff --extensions '-i' foo.c.