Sua primeira linha de comando deve funcionar sem espaços em branco:
curl -T "{file1.txt,file2.txt}" ftp://XXX/ -user YYY
Observe também o "/" no URL acima.
Este é o manual do curl sobre a opção "-T":
-T, --upload-file
This transfers the specified local file to the remote URL. If there is no file part in the specified URL, Curl will append the local file name. NOTE that you must use a trailing / on the last directory to really prove to Curl that there is no file name or curl will think that your last directory name is the remote file name to use. That will most likely cause the upload operation to fail. If this is used on an HTTP(S) server, the PUT command will be used.
Use the file name "-" (a single dash) to use stdin instead of a given file. Alternately, the file name "." (a single period) may be specified instead of "-" to use stdin in non-blocking mode to allow reading server output while stdin is being uploaded.
You can specify one -T for each URL on the command line. Each -T + URL pair specifies what to upload and to where. curl also supports "globbing" of the -T argument, meaning that you can upload multiple files to a single URL by using the same URL globbing style supported in the URL, like this:
curl -T "{file1,file2}" http://www.uploadtothissite.com
or even
curl -T "img[1-1000].png" ftp://ftp.picturemania.com/upload/
"*. txt" expansão não funciona porque curl suporta apenas a mesma sintaxe usada para URLs:
You can specify multiple URLs or parts of URLs by writing part sets within braces as in:
http://site.{one,two,three}.com
or you can get sequences of alphanumeric series by using [] as in:
ftp://ftp.numericals.com/file[1-100].txt
ftp://ftp.numericals.com/file[001-100].txt (with leading zeros)
ftp://ftp.letters.com/file[a-z].txt
[...]
When using [] or {} sequences when invoked from a command line prompt, you probably have to put the full URL within double quotes to avoid the shell from interfering with it. This also goes for other characters treated special, like for example '&', '?' and '*'.
Mas você pode usar o "normal" shell globbing assim:
curl -T "{$(echo *.txt | tr ' ' ',')}" ftp://XXX/ -user YYY
(O último exemplo pode não funcionar em todos os shells ou com qualquer tipo de nome de arquivo exótico).