[Discussion] POSIX, the Love of Backticks and All That Jazz Post: 302990520

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read

read(1) 						      General Commands Manual							   read(1)

NAME

       read - read a line from standard input

SYNOPSIS

       var ...

DESCRIPTION

       reads  a single line from standard input.  The line is split into fields as when processed by the shell (refer to shells in the first field
       is assigned to the first variable var, the second field to the second variable var, and so forth.  If there are more fields than there  are
       specified  var  operands,  the remaining fields and their intervening separators are assigned to the last var.  If there are more vars than
       fields, the remaining vars are set to empty strings.

       The setting of variables specified by the var operands affect the current shell execution environment.

       Standard input to can be redirected from a text file.

       Since affects the current shell execution environment, it is usually provided as a normal shell special (built-in) command.  Thus, if it is
       called  in  a  subshell	or  separate utility execution environment similar to the following, it does not affect the shell variables in the
       caller's environment:

   Options
       recognizes the following options:

	      Do not treat a backslash character in any special way.
		     Consider each backslash to be part of the input line.

   Opperands
       recognizes the following operands:

	      var    The name of an existing or nonexisting shell variable.

EXTERNAL INFLUENCES

   Environment Variables
       determines the internal field separators used to delimit fields.

RETURN VALUE

       exits with one of the following values:

	       0     Successful completion.

	      >0     End-of-file was detected or an error occurred.

EXAMPLES

       Print a file with the first field of each line moved to the end of the line.

	      while read -r xx yy
	      do
		      printf "%s %s 
" "$yy" "$xx"
	      done < input_file

SEE ALSO

       csh(1), ksh(1), sh(1), sh-posix(1).

STANDARDS CONFORMANCE

																	   read(1)