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| author | John Högberg <[email protected]> | 2017-11-07 09:31:24 +0100 |
|---|---|---|
| committer | John Högberg <[email protected]> | 2017-11-30 15:26:26 +0100 |
| commit | 5036bf7d5006a6f1a4294b4a3b1f4120d39113ac (patch) | |
| tree | d08757379bef5c9e5607c1da95909e4511d51cc9 /erts/doc/src | |
| parent | f5e99a55d4d62074d2bd2e5a58c578a31bc214c8 (diff) | |
| download | otp-5036bf7d5006a6f1a4294b4a3b1f4120d39113ac.tar.gz otp-5036bf7d5006a6f1a4294b4a3b1f4120d39113ac.tar.bz2 otp-5036bf7d5006a6f1a4294b4a3b1f4120d39113ac.zip | |
Add enif_ioq_peek_head
This introduces a way to retrieve erlang terms from NIF IO queues
without having to resort to copying.
OTP-14797
Diffstat (limited to 'erts/doc/src')
| -rw-r--r-- | erts/doc/src/erl_nif.xml | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index ef3cdb89e9..23f0c66429 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -367,6 +367,8 @@ return term;</code> <c>enif_ioq_deq()</c></seealso></item> <item><seealso marker="#enif_ioq_peek"> <c>enif_ioq_peek()</c></seealso></item> + <item><seealso marker="#enif_ioq_peek_head"> + <c>enif_ioq_peek_head()</c></seealso></item> <item><seealso marker="#enif_inspect_iovec"> <c>enif_inspect_iovec()</c></seealso></item> <item><seealso marker="#enif_free_iovec"> @@ -1683,8 +1685,7 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec); <fsummary>Peek inside the IO Queue</fsummary> <desc> <p>Get the I/O queue as a pointer to an array of <c>SysIOVec</c>s. - It also returns the number of elements in <c>iovlen</c>. - This is the only way to get data out of the queue.</p> + It also returns the number of elements in <c>iovlen</c>.</p> <p>Nothing is removed from the queue by this function, that must be done with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p> <p>The returned array is suitable to use with the Unix system @@ -1693,6 +1694,21 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec); </func> <func> + <name><ret>int</ret> + <nametext>enif_ioq_peek_head(ErlNifEnv *env, ErlNifIOQueue *q, size_t *size, ERL_NIF_TERM *bin_term)</nametext></name> + <fsummary>Peek the head of the IO Queue.</fsummary> + <desc> + <p>Get the head of the IO Queue as a binary term.</p> + <p>If <c>size</c> is not <c>NULL</c>, the size of the head is placed + there.</p> + <p>Nothing is removed from the queue by this function, that must be done + with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p> + <p>Returns <c>true</c> on success, or <c>false</c> if the queue is + empty.</p> + </desc> + </func> + + <func> <name><ret>size_t</ret> <nametext>enif_ioq_size(ErlNifIOQueue *q)</nametext></name> <fsummary>Get the current size of the IO Queue</fsummary> |