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NNG_CTX_SET(3) NNG Reference Manual NNG_CTX_SET(3)

NAME

nng_ctx_set - set context option

SYNOPSIS

#include <nng/nng.h>
int nng_ctx_set(nng_ctx ctx, const char *opt, const void *val, size_t valsz);
int nng_ctx_set_bool(nng_ctx ctx, const char *opt, int bval);
int nng_ctx_set_int(nng_ctx ctx, const char *opt, int ival);
int nng_ctx_set_ms(nng_ctx ctx, const char *opt, nng_duration dur);
int nng_ctx_set_size(nng_ctx ctx, const char *opt, size_t z);
int nng_ctx_set_string(nng_ctx ctx, const char *opt, const char *str);
int nng_ctx_set_uint64(nng_ctx ctx, const char *opt, uint64_t u64);

DESCRIPTION


Note

These functions are deprecated. Please see nng_ctx_set.

The nng_ctx_set() functions are used to configure options for the context ctx. The actual options that may be configured in this way vary, and are specified by opt.


Note

Context options are protocol specific.
The details will be documented with the protocol.

Forms

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_ctx_set()

This function is untyped, and can be used to configure any arbitrary data. The val pointer addresses the data to copy, and valsz is the size of the objected located at val.


Tip

It may be easier to use one of the typed forms of this function.

nng_ctx_set_bool()

This function is for options which take a Boolean (bool). The bval is passed to the option.

nng_ctx_set_int()

This function is for options which take an integer (int). The ival is passed to the option.

nng_ctx_set_ms()

This function is used to configure time durations (such as timeouts) using type nng_duration. The duration dur is an integer number of milliseconds.

nng_ctx_set_size()

This function is used to configure a size, z, typically for buffer sizes, message maximum sizes, and similar options.

nng_ctx_set_string()

This function is used to pass configure a string, str. Strings passed this way must be legal UTF-8 or ASCII strings, terminated with a NUL (\0) byte. (Other constraints may apply as well, see the documentation for each option for details.)

nng_ctx_set_uint64()

This function is used to configure a 64-bit unsigned value, u64. 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

NNG_ECLOSED

Parameter s does not refer to an open socket.

NNG_EINVAL

The value being passed is invalid.

NNG_ENOTSUP

The option opt is not supported.

NNG_EREADONLY

The option opt is read-only.

NNG_ESTATE

The socket is in an inappropriate state for setting this option.

SEE ALSO

nng_ctx_get(3), nng_socket_set(3), nng_strerror(3), nng_ctx(5), nng_options(5), nng_socket(5), nng(7)

2025-02-02