dd: error message on empty arg does not match GNU

[jfinkels]

The error message printed when dd is given an argument of, for example, bs= does not match that of GNU dd and is less clear anyway.

GNU dd:

$ dd bs=
dd: invalid number: ‘’

uutils dd:

$ ./target/release/dd bs=
./target/release/dd: Unrecognized byte multiplier -> 

[p-fuchs]

Message displayed when executing dd iflag= is:

dd: invalid input flag: ‘’
Try 'dd --help' for more information.

Should rust implementation also display Try 'dd...?

[jfinkels]

I think you are referring to the following difference between GNU dd and uutils dd; if so then yes, let's match GNU dd in this case as well:

GNU dd:

$ dd iflag=
dd: invalid input flag: ‘’
Try 'dd --help' for more information.

uutils dd:

$ ./target/debug/dd iflag=
./target/debug/dd: Unrecognized iflag=FLAG or oflag=FLAG ->