From c3e062661388f70386d6766e3ce648030af340ee Mon Sep 17 00:00:00 2001 From: Jake Woltersdorf Date: Mon, 4 Mar 2019 12:35:19 +0800 Subject: fixes #901 shorter option get/set functions for all types - Renamed internal nng_*_getx/setx methods with "nni" prefix - Moved stream get/set option definition macros to options.h and added "NNI_" prefix - "_PTR" variant of get/set option definition macros is for when first arg is passed as pointer (`nng_stream *s` vs `nng_pipe s`) - New get/set option functions for `nng_socket` are `nng_socket_get_X` eschewing the previous `nng_getopt` pattern - Macro-fy legacy getopt/setopt and implement in terms of "new" API - nng_setopt* use "new" shorter API. Add missing uint64 set functions. - Shorter get/set option functions get own man page and old getopt/setopt link to them - Built with -DNNG_ENABLE_DOC=ON and part of central libnng index - Update copyright --- docs/man/nng_pipe_get.3.adoc | 153 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 docs/man/nng_pipe_get.3.adoc (limited to 'docs/man/nng_pipe_get.3.adoc') diff --git a/docs/man/nng_pipe_get.3.adoc b/docs/man/nng_pipe_get.3.adoc new file mode 100644 index 00000000..791827b9 --- /dev/null +++ b/docs/man/nng_pipe_get.3.adoc @@ -0,0 +1,153 @@ += nng_pipe_get(3) +// +// Copyright 2019 Staysail Systems, Inc. +// Copyright 2018 Capitar IT Group BV +// +// This document is supplied under the terms of the MIT License, a +// copy of which should be located in the distribution where this +// file was obtained (LICENSE.txt). A copy of the license may also be +// found online at https://opensource.org/licenses/MIT. +// + +== NAME + +nng_pipe_get - get pipe option + +== SYNOPSIS + +[source, c] +---- +#include + +int nng_pipe_get(nng_pipe p, const char *opt, void *val, size_t *valszp); + +int nng_pipe_get_bool(nng_pipe p, const char *opt, bool *bvalp); + +int nng_pipe_get_int(nng_pipe p, const char *opt, int *ivalp); + +int nng_pipe_get_ms(nng_pipe p, const char *opt, nng_duration *durp); + +int nng_pipe_get_ptr(nng_pipe p, const char *opt, void **ptr); + +int nng_pipe_get_addr(nng_pipe p, const char *opt, nng_sockaddr *sap); + +int nng_pipe_get_string(nng_pipe p, const char *opt, char **strp); + +int nng_pipe_get_size(nng_pipe p, const char *opt, size_t *zp); + +int nng_pipe_get_uint64(nng_pipe p, const char *opt, uint64_t *u64p); + +---- + +== DESCRIPTION + +(((options, pipe))) +The `nng_pipe_get()` functions are used to retrieve option values for +the <> _p_. +The actual options that may be retrieved in this way +vary, and many are documented in <>. +Additionally some transport-specific options and protocol-specific options are +documented with the transports and protocols themselves. + +NOTE: All "`options`" on a pipe are read-only values. +Modification of options may be done before the pipe is created using +`<>` or +`<>`. + +Any option that is set on a dialer or listener will normally be retrievable +from pipes created by that dialer or listener. + +=== Forms + +In all of these forms, the option _opt_ is retrieved from the pipe _p_. + +The details of the type, size, and semantics of the option will depend +on the actual option, and will be documented with the option itself. + +`nng_pipe_get()`:: +This is untyped, and can be used to retrieve the value of any option. +A pointer to a buffer to receive the value in _val_, and the size of the +buffer shall be stored at the location referenced by _valszp_. + + + +When the function returns, the actual size of the data copied (or that +would have been copied if sufficient space were present) is stored at +the location referenced by _valszp_. +If the caller's buffer is not large enough to hold the entire object, +then the copy is truncated. +Therefore the caller should check for truncation by verifying that the +size returned in _valszp_ does not exceed the original buffer size. + + + +It is acceptable to pass `NULL` for _val_ if the value in _valszp_ is zero. +This can be used to determine the size of the buffer needed to receive +the object. + +TIP: It may be easier to use one of the typed forms of this function. + +`nng_pipe_get_bool()`:: +This function is for options which take a Boolean (`bool`). +The value will be stored at _bvalp_. + +`nng_pipe_get_int()`:: +This function is for options which take an integer (`int`). +The value will be stored at _ivalp_. + +`nng_pipe_get_ms()`:: +This function is used to retrieve time durations +(`<>`) in milliseconds, which are stored in +_durp_. + +`nng_pipe_get_ptr()`:: +This function is used to retrieve a pointer, _ptr_, to structured data. +The data referenced by _ptr_ is generally managed using other functions. +Note that this form is somewhat special in that the object is generally +not copied, but instead the *pointer* to the object is copied. + +`nng_pipe_get_size()`:: +This function is used to retrieve a size into the pointer _zp_, +typically for buffer sizes, message maximum sizes, and similar options. + +`nng_pipe_get_addr()`:: +This function is used to retrieve an `<>` +into _sap_. + +`nng_pipe_get_string()`:: +This function is used to retrieve a string into _strp_. +This string is created from the source using `<>` +and consequently must be freed by the caller using +`<>` when it is no longer needed. + +`nng_pipe_get_uint64()`:: +This function is used to retrieve a 64-bit unsigned value into the value +referenced by _u64p_. +This is typically used for options +related to identifiers, network numbers, and similar. + +== RETURN VALUES + +These functions return 0 on success, and non-zero otherwise. + +== ERRORS + +[horizontal] +`NNG_EBADTYPE`:: Incorrect type for option. +`NNG_ECLOSED`:: Parameter _p_ does not refer to an open pipe. +`NNG_ENOTSUP`:: The option _opt_ is not supported. +`NNG_ENOMEM`:: Insufficient memory exists. +`NNG_EINVAL`:: Size of destination _val_ too small for object. +`NNG_EWRITEONLY`:: The option _opt_ is write-only. + +== SEE ALSO + +[.text-left] +<> +<>, +<> +<> +<>, +<>, +<>, +<>, +<>, +<>, +<>, +<> -- cgit v1.2.3-70-g09d2