MTBL_MERGE(1)MTBL_MERGE(1)NAMEmtbl_merge - merge MTBL data from multiple input files into a single
output file
SYNOPSIS
User-provided functions:
typedef void *
(*mtbl_merge_init_func)(void);
typedef void
(*mtbl_merge_free_func)(void *clos);
typedef void
(*mtbl_merge_func)(void *clos,
const uint8_t *key, size_t len_key,
const uint8_t *val0, size_t len_val0,
const uint8_t *val1, size_t len_val1,
uint8_t **merged_val, size_t *len_merged_val);
Command line tool:
export MTBL_MERGE_DSO="libexample.so.0"
export MTBL_MERGE_FUNC_PREFIX="example_merge"
mtbl_merge [-b SIZE] [-c COMPRESSION] INPUT [INPUT]... OUTPUT
DESCRIPTIONmtbl_merge(1) is a command-line driver for the mtbl_merger(3)
interface. The mtbl_merger(3) interface requires a user-provided merge
function, which is loaded from a shared object whose filename is
specified in the environment variable MTBL_MERGE_DSO.
The user-provided merge function must have the same type as the
mtbl_merge_func function type given above in the synopsis. The symbol
name of the merge function to be loaded from the user-provided DSO will
be constructed by appending "_func" to the string provided in the
MTBL_MERGE_FUNC_PREFIX environment variable, which must be non-empty.
Additionally, two optional functions may be provided: an "init"
function whose symbol name is "_init" appended to the function prefix,
and a "free" function whose symbol name is "_free" appended to the
function prefix. If the "init" function exists, it will be called at
the beginning, before any calls to the merge function, and the return
value from the init function will be passed as the first argument to
the merge function. If the "free" function exists, it will be called at
the end, after any calls to the merge function, and its argument will
be the return value of the "init" function.
The environment variable MTBL_MERGE_BLOCK_SIZE may optionally be set in
order to configure the MTBL block size (in bytes) of the output file.
OPTIONS-b SIZE
The uncompressed data block size hint for the output file, in
bytes. The default value if unspecified is 8192 bytes (8
kilobytes).
-c COMPRESSION
The compression algorithm to use for data blocks in the output
file. The default value if unspecified is zlib. See the
mtbl_info(1) manpage for the list of possible compression
algorithms.
SEE ALSOmtbl_info(1)mtbl_merger(3)
07/21/2015 MTBL_MERGE(1)
