Linux 1>/dev/null 2> & 1 meaning shell may often see:> the result of the/dev/null 2> & 1 command can be defined in the form of %>. Output/dev/null indicates an empty Device File> indicates the redirection location, for example: echo "123">/home/123.txt 1 indicates stdout standard output. The default value is 1, therefore, ">/dev/null" is equivalent to "1>/dev/null" 2 indicating stderr standard errors & indicating equivalent meaning, 2> & 1, 2 is equivalent to 1. The statement in the title of this article: 1>/dev/null first indicates that the standard output is redirected to an empty device file, that is, no information is output to the terminal, to put it bluntly, no information is displayed. 2> & 1 next, the standard error output redirection is equivalent to the standard output. Because the standard output has been redirected to the empty device file, the standard error output is also redirected to the empty device file.