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Top Forums UNIX for Dummies Questions & Answers Problems understanding example code Post 302338883 by Scott on Wednesday 29th of July 2009 07:37:49 AM
Old 07-29-2009
Hi.

(I'm not sure if this is the technically accurate meaning, but...) set -- is used to clear or set positional arguments.

i.e.
Code:
> cat Test
set -- $(ls -l Test)
echo "\"$1\""
echo "\"$9\""
echo

set --
echo "\"$1\""
echo "\"$9\""


> ./Test a b c
"-rwx------"
"Test"

""
""

set -- will remove or overwrite args that you pass to the script (i.e. a b c in this case)

-- is commonly used by programs to signal that there are no more arguments to follow.
 

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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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