NN_SYMBOL(3) nanomsg manual NN_SYMBOL(3)NAMEnn_symbol - query the names and values of nanomsg symbols
SYNOPSIS
#include <nanomsg/nn.h>
const char *nn_symbol (int i, int *value);
DESCRIPTION
Retrieves the symbol name and value at index i. Indices start at 0. An
index has no significance to its associated symbol; the mappings may
change between library versions.
Typically a client will iterate through the symbols until nn_symbol
returns NULL in order to collect all the symbols.
All symbols exposed by nn_symbol are available directly in the C API,
generally as preprocessor macros. Thus, this function is useful mostly
for language bindings that can’t parse the header file and rely on
retrieving the symbols in the runtime.
Note that the NN_MSG symbol is not exported by the nn_symbol function.
First, it is a pointer rather than an integer; second, the symbol is
not supposed to be exported from language bindings to the user.
Instead, language bindings should provide the zero-copy functionality
in a language-specific way, if at all (zero-copy functionality may not
make sense for some languages/bindings).
RETURN VALUE
If i is valid, returns the name of the symbol at that index. If the
pointer value is not NULL, the symbol’s value is stored there.
If i is out-of-range, nn_symbol returns NULL and sets errno to EINVAL.
ERRORS
EINVAL
The passed index i was out-of-range; it was less than zero or
greater-than-or- equal-to the number of symbols.
EXAMPLE
int value, i;
for (i = 0; ; ++i) {
const char* name = nn_symbol (i, &value);
if (name == NULL) break;
printf ("'%s' = %d\n", name, value);
}
SEE ALSOnn_symbol_info(3)nn_errno(3)nn_strerror(3)nanomsg(7)AUTHORS
Evan Wies <evan@neomantra.net[1]>
NOTES
1. evan@neomantra.net
mailto:evan@neomantra.net
nanomsg Unknown 12/23/2015 NN_SYMBOL(3)
