It makes sense when you consider the effect that field splitting or pathname expansion could have. a=$1 could yield a=word1 word2 which would then execute an unintended command, word2, with a modification to its environment.
This bypassing of actions which can increase the number of tokens also occurs in the case statement: In case word in ..., word is not subject to field splitting and pathname expansion.
Quote:
Originally Posted by Corona688
Interesting disctinction. I've also noticed that IFS applies here:
Code:
set -- `cat file`
But not here:
Code:
set -- $(cat file)
I have not been able to reproduce such behavior nor have I been able to find any documentation implying that such behavior is intentional. Perhaps there's a bug in your shell? Can you specify the shell and demonstrate how you trigger such behavior?
I tried the following on bash 3.1.17 and did not observe any command substitution syntax-dependent difference in field splitting:
Code:
$ echo 1 2 3 > file
$ # With the default value of IFS, <space><tab><newline>
$ # Unquoted
$ set --; echo $#
0
$ set -- `cat file`; echo $#
3
$ set --; echo $#
0
$ set -- $(cat file); echo $#
3
$ # Quoted
$ set --; echo $#
0
$ set -- "`cat file`"; echo $#
1
$ set --; echo $#
0
$ set -- "$(cat file)"; echo $#
1
I'm having some peculiar performance issues with my Gigabit Lan.
I have some 100Mb devices so I can't do the necessary "jumbo Frame" tweaks for absolute optimum performance as I'd prevent them access.
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Whenever I sftped a particular gzipped file to a particular directory and then try to unzip it, I get Permission Denied error.
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Hi all,
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Hi!
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#!/bin/bash
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Hi ,
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lspath() {
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Discussion started by: scriptor
8 Replies
LEARN ABOUT OPENSOLARIS
noecho
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 5.11 5 Jun 2002 echo(3XCURSES)