Reporting differences between files for an ASCII comparison
When you use fc for an ASCII comparison, Windows NT reports differences
between two files by displaying the name of the first file, followed by the lines
from filename1 that differ between the files, followed by the first line to match in both
files. Windows NT then displays the name of the second file, followed by the
lines from filename2 that differ, followed by the first line to match.
Using the /b switch for binary comparisons
Windows NT uses the following format to report mismatches found during a
xxxxxxxx: yy zz
The value of xxxxxxxx specifies the relative hexadecimal address for the pair of bytes, measured
from the beginning of the file. Addresses start at 00000000; the hexadecimal
values for yy and zz represent the mismatched bytes from filename1 and filename2, respectively.
You can use wildcards (? and *) in either of the filenames you specify with
the fc command. If you use a wildcard in filename1, fc compares all the specified files to the file specified by filename. If you use a wildcard in filename2, fc uses the corresponding value from filename1.
How fc uses memory
When comparing ASCII files, fc uses an internal buffer (large enough to hold
100 lines) as storage. If the files are larger than the buffer, fc compares what
it can load into the buffer. If fc does not find a match in the loaded
portions of the files, it stops and displays the following message: