dev null 2 1

1, Introduction--From the wiki interpretation/dev/null:In a Unix-like system, a/dev/null, or empty device, is a special device file that discards everything written to it (but reports a successful write operation) and reads it immediately to get an

For details about the/dev/null and/dev/zero files, and solutions for accidental deletion of/dev/null and/dev/zero, and the disk I/O Testing Method Using/dev/zero, disk deletion and recovery by mistake1. Introduction-explanation from

This article was reprinted from: 11595985By default, there are always three files open, standard input (keyboard input), standard output (output to screen), standard error (also output to screen), and their respective file descriptors are 0,1,2. So

By default, there are always three files open, standard input (keyboard input), standard output (output to screen), standard error (also output to screen), and their respective file descriptors are 0,1,2. So let's take a look at the differences

By default, there are always three files open, standard input (keyboard input), standard output (output to screen), standard error (also output to screen), and their respective file descriptors are 0,1,2. So let's take a look at the differences

Detailed description of/dev/null and/dev/zero files, solutions for accidental deletion of/dev/null and/dev/zero, and disk I/O testing using/dev/zero1. Introduction-explanation from Wikipedia/dev/null: In Unix-like systems,/dev/null, or an empty

This article goes from http://www.kissyu.org/backgroundWe can often find such statements in a shell script >/dev/null 2>&1 . Before I did not go into the role of this command, copy replicable, until last week I wrote this order accidentally 2>&1

The shell can often be seen: >/dev/null 2>&1The result of the command can be defined in the form of a%> output/dev/null represents an empty device fileWhere does the > delegate redirect to, for example: echo "123" >/home/123.txt1 means stdout

Transfer from http://blog.chinaunix.net/uid-25100840-id-3271224.html a few days ago interview has such a question, more strange: Explain the meaning of >/dev/null 2>&1: I was scratching, also did not think out, wrote a clear buffer, hehe online

Asynchronously executes exec ("/alidata/server/php/bin/php/nas/wxdoctor/index.php App/common/wordspic/user_id/". $user _info[' user_id ']." /goods_id/". $goods _id. "." /open_id/". $user _info[' open_id '].">/dev/null 2>&1 &"); Discuss the