--- name: "rq_symbol" section: "3" platform: "linux" package: "liblcrq0.0" version: "0.2.3-1" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/rq_symbol" --- # rq\_symbol(3) generate RaptorQ encoding symbol ## NAME rq\_symbol - generate RaptorQ encoding symbol ## SYNOPSIS ``` #include ``` **int rq\_symbol(rq\_t \****rq***, rq\_pid\_t \****pid***, uint8\_t \****sym***, int** *flags***);** Compile and link with *-llcrq*. ## DESCRIPTION Generates a RaptorQ encoding symbol ready for sending. Before calling **rq\_symbol()** the intermediate symbols must first be created with a call to [**rq\_encode**(3)](/rq_encode/3.md). *rq* must be a pointer to valid **rq\_t** context *pid* will be set to the FEC payload ID as per Section 3.2 of RFC6330: ``` 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SBN | Encoding Symbol ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ``` SBN (Source Block Number) is an 8 bit unsigned integer. The Encoding Symbol ID (ESI) is a 24 bit unsigned integer in network byte order. On success, *sym* will be a pointer to the encoding symbol. *flags* can be set to: - **RQ\_RAND** Generate a random repair symbol instead of returning the next ESI. ## RETURN VALUE Returns a pointer to the encoded symbol. ## ERRORS None. ## SEE ALSO [**rq\_init**(3)](/rq_init/3.md), [**rq\_free**(3)](/rq_free/3.md), [**rq\_encode**(3)](/rq_encode/3.md), [**rq\_decode**(3)](/rq_decode/3.md), [**rq\_query**(3)](/rq_query/3.md), [**lcrq**(7)](/lcrq/7.md), [**errno**(3)](/errno/3.md)