Alternative use of the Copy command

In the DOS era, the copy command is probably the most popular and commonly used dos internal command, but in today's windows, it is gradually forgotten by users and seems dispensable. In fact, this command is far more than just "copy". Using it will produce unexpected results.

Remote upload and download using copy

Everyone knows how to copy files using the Copy command, but do you know? Copy also supports remote file copying! For example, copy C:/srv. EXE // 210. ***. ***. * **/ADMIN $ you can set the program srv. EXE "Upload" to the ADMIN $ shared directory of the other party. Of course, this can also be done in turn, and it will become "Download": Copy // 210. ***. ***. * **/ADMIN $/srv. exe c: // you can share the SRV under the ADMIN $ shared directory of the other party. download the EXE file to the local drive C.

Using copy to hide secrets in others' stomachs

The Copy command of DOS can combine several files of the same type into one file. For example, multiple. txt files can also be used to merge a text file into a non-text file, implement the effect of hiding secrets. For example, if you have an important text file 001.txtin the root directory of drive D, you want to hide it.
Find an MP3 song, preferably not too large (around KB), for example: wanfei.pdf (assuming it is also placed in the root directory of the d disk), input: Copy wanfei.pdf/B + 001.txt/ A wanfei-1.mp3, this will generate a new file wanfe. Open it with Winamp, and the song remains unchanged. Press the shiftkey to right-click wanfei-1.mp3, select "open mode", and select a text editor such as emeditor to open the file. What do you see? A bunch of garbled characters? But if you press the ctrl+endcombination key to move the cursor to the end of the file, is it not the content of the 001.txt file?
Note: Parameter/B Indicates copying and merging files in binary format. Parameter/A indicates copying and merging files in ASCII format. Pay attention to the file sequence. Files in binary format should be placed before the plus sign, and files in text format should be placed behind the plus sign. One thing to note: it is better to leave at least three lines in front of the text file so that the content in its header is not easy to lose.

In the same way, you can hide files in images, WAV audio files, or even Word, Excel, and other documents. For example:
Copy wanfei.jpg/B + 001.txt/ A wanfei-1.jpg(add 001.txtto the image wanfei-1.jpg)
Copy wanfei.doc/B + 001.txt/ A wanfei-1.doc(hide 001.txtinto the wanfei-1.doc document)
Copy wanfei.wav/B + 001.txt/ A wanfei-1.wav(bring 001.txtto the wanfei-1.wav file)
Copy wanfei.exe/B + 001.txt/ A wanfei-1.exe(hide 001.txtinto the wanfei-1.exe file)