hadd(1)

SYNOPSIS
usage: hadd [-a] [-f] [-f[0-9]] [-fk] [-ff] [-k] [-L] [-Ltype] [-O] [-T]
            [-v V] [-j J] [-dbg] [-d D] [-n N] [-cachesize CACHESIZE]
            [-experimental-io-features EXPERIMENTAL_IO_FEATURES]
            TARGET SOURCES

DESCRIPTION
This program will add histograms, trees and other objects from a list of ROOT files and write them to a target ROOT file. The target file is newly created and must not exist, or if -f ("force") is given, must not be one of the source files.

OPTIONS

-a  Append to the output

-f  Force overwriting of output file

-f[0-9]
    Gives the ability to specify the compression algorithm i and level j

    of the target file, by passing the number i*100 + j, e.g. -f505. The

    last digit (j) can be set from 0 = uncompressed to 9 = highly

    compressed. The first digit (i) is 1 for ZLIB, 2 for LZMA, 4 for LZ4

    and 5 for ZSTD. Recommended numbers are 101 (ZLIB), 207 (LZMA), 404

    (LZ4), 505 (ZSTD). The default value for this flag is 101

    (kDefaultZLIB). See ROOT::RCompressionSetting and TFile::TFile

    documentation for more details.

-fk Sets the target file to contain the baskets with the same compression

    as the input files (unless -O is specified). Compresses the meta data

    using the compression level specified in the first input or the

    compression setting after fk (for example 206 when using -fk206)

-ff The compression level use is the one specified in the first input

-k  Skip corrupt or non-existent files, do not exit

-L  Read the list of objects from FILE and either only merge or skip those

    objects depending on the value of "-Ltype". FILE must contain one

    object name per line, which cannot contain whitespaces or '/'. You can

    also pass TDirectory names, which apply to the entire directory

    content. Lines beginning with '#' are ignored. If this flag is passed,

    "-Ltype" MUST be passed as well.

-Ltype
    Sets the type of operation performed on the objects listed in FILE

    given with the "-L" flag. "SkipListed" will skip all the listed

    objects; "OnlyListed" will only merge those objects. If this flag is

    passed, "-L" must be passed as well.

-O  Re-optimize basket size when merging TTree

-T  Do not merge Trees

-v  Explicitly set the verbosity level: 0 request no output, 99 is the

    default

-j  Parallelize the execution in 'J' processes. If the number of processes

    is not specified, use the system maximum.

-dbg
    Enable verbosity. If -j was specified, do not not delete partial files

    stored inside working directory.

-d  Carry out the partial multiprocess execution in the specified

    directory

-n  Open at most 'N' files at once (use 0 to request to use the system

    maximum)

-cachesize
    Resize the prefetching cache use to speed up I/O operations (use 0 to

    disable)

-experimental-io-features
    Used with an argument provided, enables the corresponding experimental

    feature for output trees. See ROOT::Experimental::EIOFeatures

TARGET
    Target file

SOURCES
    Source files