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Full Discussion: Confusion about IFS Variable
Top Forums Shell Programming and Scripting Confusion about IFS Variable Post 302172831 by Perderabo on Tuesday 4th of March 2008 08:16:47 PM
Old 03-04-2008
A script like:
#! /bin/sh
echo hello | read word ; echo word = $word
will work on HP-UX but fail on Linux. HP's /bin/sh is a modified version of the real Korn shell. But Linux's /bin/sh is a linked version of bash. The real Korn shell is the only shell that executes the last command of a pipeline in the context of the current shell provided that the last command is a shell built-in. Other shells will fork a new process to handle that "read word". The subprocess will exit and back in the parent, the variable "word" never got a new value. Beware: Linux often has pd-ksh which will behave the same way.
 

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LEARN ABOUT SUSE

sg

newgrp(1)						      General Commands Manual							 newgrp(1)

NAME

       newgrp -  change effective group ID sg - execute command with different group ID

SYNOPSIS

       newgrp [-l] [group]
       sg group -c command

DESCRIPTION

       The  newgrp  command changes the user's real and effetive group ID by replacing the current shell with a new shell. A new shell is launched
       even if an error occours.

       A password is requested if the group has a password and the user is not listed in the group file as being a member of that group. The pass-
       word can be changed with the gpasswd(1) command.

       If the new effective group ID is not in the supplementary group list, newgrp will add the new group ID to the supplementary list, too.

       With  no  operands  and options, newgrp changes the user's group IDs (real and effective) back to the group specified in password and group
       file.

       The sg command works like the newgrp command, except that it executes the given command with /bin/sh and upon exit the group ID of the cur-
       rent shell is not changed.

OPTIONS

       -l, --login
	      reinitialize the environment as if the user logged in.

       --help Print a help list.

       -u, --usage
	      Print a short usage message.

       -v, --version
	      Print program version.

SEE ALSO

       gpasswd(1), group(5), passwd(1), passwd(5), su(1)

AUTHOR

       Thorsten Kukuk <kukuk@suse.de>

pwdutils							    April 2004								 newgrp(1)
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