[LU-8621] Parser_execarg() prints help to stderr, usage to stdout

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.16.0
• Labels: easy utils
• Severity: 3
• Assignee: Aleksei Alyaev (Inactive)
• Reporter: John Hammond

Description

When running lfs CMD --help or lctl CMD --help the help message is printed to stderr. By convention stdout should be used instead.

When using lfs or lctl, if an unrecognized command is passed to Parser_execarg() we get a 100+ line usage message printed to stdout.

# lctl barf
Try interactive use without arguments or use one of:
"===== metacommands ======="
"--device"
"--ignore_errors"
"ignore_errors"
"======== control ========="
"help"
"lustre_build_version"
"exit"
"quit"
...
"llog_print"
"llog_check"
"llog_cancel"
"llog_remove"
"add_interface"
"del_interface"
"add_route"
"del_route"
"set_route"
as argument.

1. We shouldn't spam the terminal with so many lines of output for an unrecognized command.
2. We need to print the command that was passed.

   # git barf
   git: 'barf' is not a git command. See 'git --help'.
   
   Did you mean this?
   	branch
   

Issue Links

• is related to: LU-16392 Bash completion regressions, lctl and lfs