Re: [alsa-devel] [PATCH - alsa-lib 1/1] Introduce snd_seq_client_info_get_card_number, for getting the card number of a seq client on recent kernels

Adam Goode wrote:

/**

• • \brief Get the card number of a client_info container
• • \param info client_info container
• • \return the card number, -1 if no card associated with this client, or -ENOSYS if the

• •     kernel does not support reporting this field
    

• */

-1 is used as an out-of-range value when enumerating cards. However, I don't think this convention can be applied here, because the return value is also used for error codes, and -1 would correspond to -EPERM.

Squashing all error codes into -1 is not a good idea, so I think the value -1 should be converted into an appropriate error code, probably -ENXIO.

Regards, Clemens