UIPEthernet: A plugin-replacement of the stock Arduino Ethernet library for ENC28J60 shields and breakout boards. Full support for persistent (streaming) TCP-connections and UDP (Client and Server each), ARP, ICMP, DHCP and DNS. Build around Adam Dunkels uIP Stack. Further developed version can be found on https://github.com/UIPEthernet/UIPEthernet
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read and readBytes have different returns value when there is no data #149
I have been integrating the library in a project that uses the readBytes function from a TCP Client. It was hard to find a problem related with the return value of readBytes, that seems to behave different than using the read function.
For example:
int read = client_.readBytes(buffer, size);
int read = client_.read(buffer, size);
Will return 1 and 0 respectively when trying to read a single byte from the card and there is no available data, as available() returns 0. I was expecting readBytes to return also 0, and no 1, as no data was read.
I have been trying to detect the problem in the code, but without luck. The function int UIPClient::read(uint8_t *buf, size_t size) is working fine as it is returning 0 bytes read both when calling readBytes or read, but there should be something more out there that is changing the value.
I have been integrating the library in a project that uses the
readBytesfunction from a TCP Client. It was hard to find a problem related with the return value ofreadBytes, that seems to behave different than using thereadfunction.For example:
Will return 1 and 0 respectively when trying to read a single byte from the card and there is no available data, as
available()returns 0. I was expectingreadBytesto return also 0, and no 1, as no data was read.I have been trying to detect the problem in the code, but without luck. The function
int UIPClient::read(uint8_t *buf, size_t size)is working fine as it is returning 0 bytes read both when calling readBytes or read, but there should be something more out there that is changing the value.Thanks.