what does the operation '>&' mean in a shell script

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1

hi, all,

i saw a syntax like this

usr/local/mpiexec -np 8 /home/XXXX/program_exe >& ./temp/out

the output will be put into ./temp/out.

I want to know the meaning of the operation symbol '>&'.

Thanks

2

It redirects standard error as well as standard output to the file in question.

See the manual page of your shell for detailed information about redirection operators.

3

in that case,
shouldn't that be as
>1 2>&1

4

It should, but it's available as a shorthand at least in bash. The manual discourages this use. I imagine it's offered for compatibility with older shells.