2 >&1 redirects standard error to standard output. &1 indicates file descriptor (standard output), otherwise (if you use just 1 ) you will ... ... <看更多>

/dev/null 2>&1. Output redirection. The greater-thans (>) in commands like these redirect the program's output somewhere. In this case, something is being ... ... <看更多>

2 >&1 is asking to direct all the STDERR as STDOUT , (ie. to treat all the error messages generated from the script as its standard output). Now ... ... <看更多>

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