11-10-2008
cat /dev/null gives an empty string without a newline just like echo -n "" so you won't get any output.
awk gets a line in the buffer, only if it ends with a newline.
Regards
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ECHO(1) FSF ECHO(1)
NAME
echo - display a line of text
SYNOPSIS
echo [OPTION]... [STRING]...
DESCRIPTION
NOTE: your shell may have its own version of echo which will supercede the version described here. Please refer to your shell's documenta-
tion for details about the options it supports.
Echo the STRING(s) to standard output.
-n do not output the trailing newline
-e enable interpretation of the backslash-escaped characters listed below
-E disable interpretation of those sequences in STRINGs
--help display this help and exit
--version
output version information and exit
Without -E, the following sequences are recognized and interpolated:
NNN the character whose ASCII code is NNN (octal)
\ backslash
a alert (BEL)
backspace
c suppress trailing newline
f form feed
new line
carriage return
horizontal tab
v vertical tab
AUTHOR
Written by FIXME unknown.
REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.
COPYRIGHT
Copyright (C) 2002 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
LAR PURPOSE.
SEE ALSO
The full documentation for echo is maintained as a Texinfo manual. If the info and echo programs are properly installed at your site, the
command
info echo
should give you access to the complete manual.
GNU coreutils 4.5.3 February 2003 ECHO(1)