Difference between xcopy and robocopy

I'm kind of new to batch scripting. As a newbie I find both both of them useful while scripting What are the key differences between xcopy and robocopy?


Robocopy replaces XCopy in the newer versions of windows

  1. Uses Mirroring, XCopy does not
  2. Has a /RH option to allow a set time for the copy to run
  3. Has a /MON:n option to check differences in files
  4. Copies over more file attributes than XCopy

Yes i agree with Mark Setchell, They are both crap. (brought to you by Microsoft)


UPDATE:

XCopy return codes:

0 - Files were copied without error.
1 - No files were found to copy.
2 - The user pressed CTRL+C to terminate xcopy. enough memory or disk space, or you entered an invalid drive name or invalid syntax on the command line.
5 - Disk write error occurred.

Robocopy returns codes:

0 - No errors occurred, and no copying was done. The source and destination directory trees are completely synchronized.
1 - One or more files were copied successfully (that is, new files have arrived).
2 - Some Extra files or directories were detected. No files were copied Examine the output log for details. 
3 - (2+1) Some files were copied. Additional files were present. No failure was encountered.
4 - Some Mismatched files or directories were detected. Examine the output log. Some housekeeping may be needed.
5 - (4+1) Some files were copied. Some files were mismatched. No failure was encountered.
6 - (4+2) Additional files and mismatched files exist. No files were copied and no failures were encountered. This means that the files already exist in the destination directory
7 - (4+1+2) Files were copied, a file mismatch was present, and additional files were present.
8 - Some files or directories could not be copied (copy errors occurred and the retry limit was exceeded). Check these errors further.
16 - Serious error. Robocopy did not copy any files. Either a usage error or an error due to insufficient access privileges on the source or destination directories.

There is more details on Robocopy return values here: http://ss64.com/nt/robocopy-exit.html


The most important difference is that robocopy will (usually) retry when an error occurs, while xcopy will not. In most cases, that makes robocopy far more suitable for use in a script.

Addendum: for completeness, there is one known edge case issue with robocopy; it may silently fail to copy files or directories whose names contain invalid UTF-16 sequences. If that's a problem for you, you may need to look at third-party tools, or write your own.


The differences I could see is that Robocopy has a lot more options, but I didn't find any of them particularly helpful unless I'm doing something special.

I did some benchmarking of several copy routines and found XCOPY and ROBOCOPY to be the fastest, but to my surprise, XCOPY consistently edged out Robocopy.

It's ironic that robocopy retries a copy that fails, but it also failed a lot in my benchmark tests, where xcopy never did.

I did full file (byte by byte) file compares after my benchmark tests.

Here are the switches I used with robocopy in my tests:

 **"/E /R:1 /W:1 /NP /NFL /NDL"**.  

If anyone knows a faster combination (other than removing /E, which I need), I'd love to hear.

Another interesting/disappointing thing with robocopy is that if a copy does fail, by default it retries 1,000,000 times with a 30 second delay between each try. If you are running a long batch file unattended, you may be very disappointed when you come back after a few hours to find it's still trying to copy a particular file.

The /R and /W switches let you change this behavior.

  • With /R you can tell it how many times to retry,
  • /W let's you specify the wait time before retries.

If there's a way to attach files here, I can share my results.

  • My tests were all done on the same computer and
  • copied files from one external drive to another external,
  • both on USB 3.0 ports.

I also included FastCopy and Windows Copy in my tests and each test was run 10 times. Note, the differences were pretty significant. The 95% confidence intervals had no overlap.