What does the following mean ?
diff -rBNu src.orig/java/org/apache/nutch/analysis/NutchAnalysisConstants.java src/java/org/apache/nutch/analysis/NutchAnalysisConstants.java
--- src.orig/java/org/apache/nutch/analysis/NutchAnalysisConstants.java 2009-03-10 11:34:01.000000000 -0700
+++ src/java/org/apache/nutch/analysis/NutchAnalysisConstants.java 2009-03-10 14:11:55.000000000 -0700
@@ -4,9 +4,12 @@
+ int CJK = 21;
+ int DIGIT = 22;
int DEFAULT = 0;
String[] tokenImage = {
"<EOF>",
+ "\"OR\"",
"<WORD>",
"<ACRONYM>",
"<SIGRAM>",
@@ -39,6 +42,8 @@
"\"\\\"\"",
"\":\"",
"\"/\"",
+ "\"(\"",
+ "\")\"",
"\".\"",
"\"@\"",
"\"\\\'\"",
Best Answer
The
-u
option you used specifies the unified format. In that format the first two lines is a header:---
is the original file,+++
is the new file, and the timestamps.@@
block headersThat is then followed by chunks (change hunks) that starts with the
@@ -R,r +R,r @@
syntax.Those are two ranges, the one with the
-
is the range for the chunk in the original file, and the one with the+
the range in the new file. TheR
designates the line number where the diff operation is started.The numbers after the comma are the number of affected lines in each file.
+r
number will be smaller than-r
.+r
number will be bigger than-r
0
to the+r
number. (same scope of lines)Chunks of code lines
Within these chunks lines are identified as additions or deletions
-
means delete,+
means addition. Lines that did not change in that chunk will have neither+
or-
front of it.In your example it means there are two chunks, or sections, that changed between the two files and the lines with
+
in it are the new ones added, nothing was deleted.You can find much more information about the syntax by doing a google search for unified diff.