HP-UX Reference (11i v1 05/09) - 1 User Commands N-Z (vol 2)

read(1) read(1)

NAME

read - read a line from standard input

SYNOPSIS

read [-r] var ...

DESCRIPTION

read reads a single line from standard input. The line is split into ﬁelds as when processed by the shell

(refer to shells in SEE ALSO); 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

read can be redirected from a text ﬁle.

Since read 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:

(read foo)

nohup read ...

find . -exec read ... ;

Options and Arguments

read recognizes the following options and command-line arguments:

-r Do not treat a backslash character in any special way. Consider each backslash to be

part of the input line.

var The name of an existing or non-existing shell variable.

EXTERNAL INFLUENCES

Environment Variables

IFS determines the internal ﬁeld separators used to delimit ﬁelds.

RETURN VALUE

read 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

printf "%s %s \n" "$yy" "$xx"

done < input_file