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Full Discussion: Bash : Why are spaces important here ?
Top Forums Shell Programming and Scripting Bash : Why are spaces important here ? Post 302932225 by balajesuri on Tuesday 20th of January 2015 05:02:05 AM
Old 01-20-2015
Quote:
Originally Posted by John K
BTW ..What is ++ operator as in (( ++count )) called ?
It's known as a pre-increment operator. It means, first increment the value in count and then use it.
On the contrary, there's a post-increment operator ((count++)); which means use it first and then increment it.

It will be clear in the following example:
Code:
[user@host ~]$ x=1
[user@host ~]$ y=$((++x))
[user@host ~]$ echo $x $y
2 2
[user@host ~]$ x=1
[user@host ~]$ y=$((x++))
[user@host ~]$ echo $x $y
2 1
[user@host ~]$

These 2 Users Gave Thanks to balajesuri For This Post:
John K rbatte1
 

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LEARN ABOUT OSF1

ruserok

ruserok(3)						     Library Functions Manual							ruserok(3)

NAME

       ruserok -  Allows servers to authenticate clients

LIBRARY

       Standard C Library (libc.a)

SYNOPSIS

       #include <unistd.h>

       int ruserok (	  char *host,	   int root_user,      char *remote_user,      char *local_user );

PARAMETERS

       Specifies  the name of a remote host.  Specifies a value to indicate whether the effective user ID of the calling process is that of a root
       user.  A value of 0 (zero) indicates the process does not have a root user ID.  A value of 1 indicates that the process has local root user
       privileges, and the /etc/host.equiv file is not checked.  Points to a username that is valid at the remote host.  Any valid username can be
       specified.  Points to a username that is valid at the local host.  Any valid username can be specified.

DESCRIPTION

       The ruserok() (remote command user OK) function allows servers to authenticate clients requesting services.

       The hostname must be specified.	If the local domain and remote domain are the same, specifying the domain parts is optional.  To determine
       the domain of the host, use the gethostname() function.	The ruserok() function checks for this host in the /etc/host.equiv file.  Then, if
       necessary, the subroutine checks a file in the user's home directory at the server called $HOME/.rhosts for a host and remote user ID.

RETURN VALUES

       The ruserok() function returns 0 (zero) if  the	subroutine  successfully  locates  the	name  specified  by  the  host	parameter  in  the
       /etc/hosts.equiv file or if the IDs specified by the host and remote_user parameters are found in the $HOME/.rhosts file.

       If the name specified by the host parameter was not found, the ruserok() function returns a value of -1.

FILES

       Contains service names.	Specifies foreign hostnames.  Specifies the remote users of a local user account.

RELATED INFORMATION

       Functions: gethostname(2), rcmd(3), rresvport(3), sethostname(2)

       Commands: rlogind(8), rshd(8) delim off

																	ruserok(3)
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