Does the COSCMD tool support regular expressions?
No.
I can successfully create a bucket with a name containing uppercase letters using COSCMD tool, but when I perform other operations with a bucket name containing uppercase letters, an error occurs. What is the reason for this?
The COSCMD tool automatically converts uppercase letters to lowercase ones. A bucket name can only contain lowercase letters, numbers, and hyphen (-), with a length not greater than 40 characters. For more information, see Use Limits.
Can the files in a sub-directory be excluded when I download the files in the root directory with COSCMD tool?
Yes. You can filter our files using coscmd download --ignore /folder/*. If you need to ignore the folder with a certain suffix, be sure to append , to the "*" character, or enclose it with "".