xenial (3) buffer_get_token_sa_pred.3.gz

NAME

       buffer_get_token_sa_pred - read token from buffer

SYNTAX

       #include <stralloc.h>
       #include <buffer.h>

       int buffer_get_token_sa_pred(buffer* b,stralloc* sa,
                        int (*predicate)(stralloc* * sa));

DESCRIPTION

       buffer_get_token_sa_pred appends data from b to sa until predicate(sa) returns 1 or -1.

       If  predicate  returns  1  once  a  '\n' was read, that new-line character is still appended to sa -- use
       stralloc_chop or stralloc_chomp to get rid of it.  predicate can also return 0 (indicating further  input
       is  required  to  complete the token) or -1 (abort and return -1; use this if predicate wants to enfore a
       maximum message size or does timeout handling or detects a malformed message).

       If reading from the buffer or allocating memory fails, buffer_get_token_sa_pred returns -1 and sets errno
       appropriately.  At that point sa may already contain a partial token.

       On success, buffer_get_token_sa_pred returns 0.

RATIONALE

       buffer_get_token_sa_pred  appends instead of overwriting so it can be used on non-blocking sockets (these
       signal error and set errno to EAGAIN; in this case you can simply  call  buffer_get_token_sa  again  when
       select or poll indicate more data is available).

SEE ALSO

       buffer_getline_sa(3), buffer_get_token(3), buffer(3)

                                                                                     buffer_get_token_sa_pred(3)