18.3.53. pmix_regex2_t

pmix_regex2_t — A compact, self-describing encoding of an ordered list of values (for example, node or process names).

18.3.53.1. SYNTAX

18.3.53.1.1. C Syntax

#include <pmix_common.h>

typedef struct pmix_regex2 {
    char *type;         // colon-delimited identifier of the encoding method (e.g., "pmix" or "blob")
    uint8_t *bytes;     // encoded representation (may not be NULL-terminated)
    size_t len;         // number of bytes in the encoded representation
} pmix_regex2_t;

18.3.53.2. DESCRIPTION

The pmix_regex2_t structure holds a reduced-size, encoded representation of an ordered list of values — most commonly the set of node names, or the set of process names, that participate in a job. Encoding a long, regular list (such as node000,node001,...,node511) into this compact form greatly reduces the volume of data that must be exchanged when a namespace is registered or distributed.

The fields are:

type — A colon-delimited string naming the encoding method used to produce the representation (for example, "pmix" for the built-in regular expression generator, or "blob" for an opaque payload). The parser uses this identifier to select the matching decoder.
bytes — The encoded representation itself. This is a raw byte buffer and is not guaranteed to be NULL-terminated; its length is given by len.
len — The number of bytes in the bytes buffer.

A pmix_regex2_t is produced by PMIx_generate_regex2(3) from a comma-separated input string, and is expanded back into the original list by PMIx_parse_regex2(3). The order of the individual values is preserved across the generate/parse round trip. The encoded form may also be passed to PMIx_server_register_nspace(3) for processing. In all cases the caller is responsible for releasing the data the structure references.

The pmix_regex2_t type supersedes the older raw char* regular-expression form. It also appears as a member of the pmix_value_t(5) union so that an encoded list can be carried as a typed value.

18.3.53.3. STATIC INITIALIZER

A statically declared pmix_regex2_t may be initialized with the PMIX_REGEX2_STATIC_INIT macro, which sets type and bytes to NULL and len to 0:

pmix_regex2_t regex = PMIX_REGEX2_STATIC_INIT;