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Top Forums UNIX for Dummies Questions & Answers Redirection of file input to command Post 302856179 by wisecracker on Monday 23rd of September 2013 09:28:27 AM
Old 09-23-2013
Again longhand to demonstrate...
Code:
Last login: Mon Sep 23 14:05:22 on ttys000
AMIGA:barrywalker~> text="This is a line."
AMIGA:barrywalker~> echo -n "$text" > /tmp/txt
AMIGA:barrywalker~> read newtext < /tmp/txt
AMIGA:barrywalker~> echo "$newtext"
This is a line.
AMIGA:barrywalker~> # Use echo direct.
AMIGA:barrywalker~> echo < /tmp/txt

AMIGA:barrywalker~> # Nothing!
AMIGA:barrywalker~> # Now attempt to force into a variable.
AMIGA:barrywalker~> oldtext=$(echo < /tmp/txt)
AMIGA:barrywalker~> # Check "oldtext".
AMIGA:barrywalker~> echo "$oldtext"

AMIGA:barrywalker~> # Again nothing.
AMIGA:barrywalker~> # Now check the variable length.
AMIGA:barrywalker~> echo ${#oldtext}
0
AMIGA:barrywalker~> # As you can see no characters.
AMIGA:barrywalker~> _

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echo(3XCURSES)						  X/Open Curses Library Functions					    echo(3XCURSES)

NAME
echo, noecho - enable/disable terminal echo SYNOPSIS
cc [ flag... ] file... -I /usr/xpg4/include -L /usr/xpg4/lib -R /usr/xpg4/lib -lcurses [ library... ] c89 [ flag... ] file... -lcurses [ library... ] #include <curses.h> int echo(void); int noecho(void); DESCRIPTION
The echo() function enables Echo mode for the current screen. The noecho() function disables Echo mode for the current screen. Initially, curses software echo mode is enabled and hardware echo mode of the tty driver is disabled. The echo() and noecho() functions control soft- ware echo only. Hardware echo must remain disabled for the duration of the application, else the behavior is undefined. RETURN VALUES
Upon successful completion, these functions return OK. Otherwise, they return ERR. ERRORS
No errors are defined. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |Unsafe | +-----------------------------+-----------------------------+ SEE ALSO
getch(3XCURSES), getstr(3XCURSES), initscr(3XCURSES), libcurses(3XCURSES), scanw(3XCURSES), attributes(5), standards(5) SunOS 5.10 5 Jun 2002 echo(3XCURSES)
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