Linux Command: cp -f, --force, Not Working

Today, when I tried to copy some files from one dirctory to the other in my Linux server, I issued the following Linux command:

#>cp -rf /dir1/* /dir2

However, the -f, --force switch, which was to tell cp command to overwrite the existing files (it meas if an existing destination file cannot be opened, remove it and try again), did not seen to work. I kept getting the following message:

cp: overwrite ‘/dir1/subdir1/file.dat with /dir2/subdir1/file.dat’

Since I had about 300 files to copy, it was not easy for me to keep typing ‘y’. So, I did some searches and found the following solution.

1. Run the alias command to check if cp was set to alias with a different command.

#> alias

alias cp='cp -i'
alias mv='mv -i'
alias rm='rm -i'

Which you can see, cp was acturaly alias as 'cp –i'. -i, --interactive, which means prompt before overwrite. Therefore, -f was ignored.

I want to remove the alias so I could copy the files. To do so, I needed to issue the following command:

#>unalias cp

However, in normally situation, we do want to use cp –i to prevent accidentally override files. Therefore, I issued the following command after done with copying the files:

#>alias ‘cp=cp –I’

One more detail, to perform the above steps, it required root access. So, what happen if we don’t have root access? Well, the following command works:

Command:
#> /bin/cp -rf /dir1/* /dir2

It is because that the /bin/cp copy is not alias to any other command switch.

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