Trivial Description
Running "mapred pipes" returns:
bin/hadoop pipes [-input <path>] // Input directory [-output <path>] // Output directory [-jar <jar file> // jar filename [-inputformat <class>] // InputFormat class [-map <class>] // Java Map class [-partitioner <class>] // Java Partitioner [-reduce <class>] // Java Reduce class [-writer <class>] // Java RecordWriter [-program <executable>] // executable URI [-reduces <num>] // number of reduces [-lazyOutput <true/false>] // createOutputLazily
No Hadoop CLI uses // comments in the help. Most of them follow the
pattern similar to UNIX/Linux man page styling:
usage: CMD OPTIONS OPTIONS/SUBCMD-BLOCK OPTION/SUBCMD-DEFINITION-BLOCK
It should be look like this since the comments are really redundant:
usage: bin/mapred pipes [-input <path>] [-output <path>] [-jar <jar file>] [-inputformat <class>] [-map <class>] [-partitioner <class>] [-reduce <class>] [-writer <class>] [-program <executable URI>] [-reduces <num>] [-lazyOutput <true/false>]
then the parameters can be expanded upon in the section below.