Why does the command `run` fails in this example from the documentation?

I am trying to learn how to issue shell commands from my Julia program. My OS is Windows 10 but I would also like the commands to run under Linux (Kubuntu). I found the following in the documentation:

julia> mycommand = `echo hello`
`echo hello`

julia> typeof(mycommand)

julia> run(mycommand);

The two first commands run as displayed above, but when I try the last one I get the following:

julia> run(mycommand);
ERROR: IOError: could not spawn `echo hello`: no such file or directory (ENOENT)
 [1] _spawn_primitive(file::String, cmd::Cmd, stdio::Vector{Any})
   @ Base .\process.jl:99
 [2] #637
   @ .\process.jl:112 [inlined]
 [3] setup_stdios(f::Base.var"#637#638"{Cmd}, stdios::Vector{Any})
   @ Base .\process.jl:196
 [4] _spawn
   @ .\process.jl:111 [inlined]
 [5] run(::Cmd; wait::Bool)
   @ Base .\process.jl:439
 [6] run(::Cmd)
   @ Base .\process.jl:438
 [7] top-level scope
   @ REPL[19]:1


I would like to understand why this happened, and more generally how to issue Windows command prompt commands like dir, md, cd, etc. from inside my Julia program. Same for Linux.

Any help will be greatly appreciated.


; cmd /c echo hello

shell>  cmd /c echo hello

The following assumes a Posix environment as on Linux or MacOS. On Windows, many similar commands, such as echo and dir , are not external programs and instead are built into the shell cmd.exe itself. One option to run these commands is to invoke cmd.exe , for example cmd /C echo hello . Alternatively Julia can be run inside a Posix environment such as Cygwin.


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