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# hdfs.download

Copies a file from HDFS to the local file system.

Usage

    hdfs.download(
            dfs.id,
            filename,
            overwrite)

Arguments

dfs.id

  The name of a file in HDFS. The file name can include a path that is either absolute or relative to the current path.

filename

  The name of a file in the local file system where the data is copied.

overwrite

  Controls whether the operation can overwrite an existing local file. Set to `TRUE` to overwrite `filename`, or `FALSE` to signal an error (default).

Usage Notes

This function provides the fastest and easiest way to copy a file from HDFS. No data transformations occur except merging multiple parts into a single file. The local file has the exact same data as the HDFS file.

Return Value

Local file name, or `NULL` if the copy failed

Example

This example displays a list of files in the current HDFS directory and copies ontime2000.DB to the local file system as /home/oracle/ontime2000.dat.

    R> hdfs.ls()
    [1] "ontime2000_DB" "ontime_DB"     "ontime_File"   "ontime_R"      "testdata.dat"
    R> tmpfile <- hdfs.download("ontime2000_DB", "/home/oracle/ontime2000.dat", overwrite=F)
    R> tmpfile
    [1] "/home/oracle/ontime2000.dat"