read(1) read(1)
NAME [Toc] [Back]
read - read a line from standard input
SYNOPSIS [Toc] [Back]
read [-r] var ...
DESCRIPTION [Toc] [Back]
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 [Toc] [Back]
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 [Toc] [Back]
Environment Variables
IFS determines the internal field separators used to delimit fields.
RETURN VALUE [Toc] [Back]
read exits with one of the following values:
0 Successful completion.
Hewlett-Packard Company - 1 - HP-UX 11i Version 2: August 2003
read(1) read(1)
>0 End-of-file was detected or an error occurred.
EXAMPLES [Toc] [Back]
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 \n" "$yy" "$xx"
done < input_file
SEE ALSO [Toc] [Back]
csh(1), ksh(1), sh-posix(1), sh(1).
STANDARDS CONFORMANCE [Toc] [Back]
read: SVID2, XPG2, XPG3, XPG4, POSIX.2 FIPS
Hewlett-Packard Company - 2 - HP-UX 11i Version 2: August 2003 [ Back ] |