$_ :- Is a Special variable set to last argument of previous command executed.
Examples:-
Code:
#!/bin/bash
echo $_ # /bin/bash
# Just called /bin/bash to run the script.
du >/dev/null # So no output from command.
echo $_ # du
ls -al >/dev/null # So no output from command.
echo $_ # -al (last argument)
:
echo $_ # :
#!/bin/sh
$ORACLE_HOME/bin/sqlplus -S $orauserid/$orapasswd@$oradb << _TMP
alter session set nls_date_format = 'YYYYMMDD HH24:MI';
set linesize 100
set pagesize 400
ok the above is part of a script..i just wanna know what does sqlplus -S means?? as in why we need to insert the -S behind? (2 Replies)
Masters,
I am trying to learn the serial mouse driver for linux kernel. On the kernel source tree I find out these macros and I am unable to find out the meaning of these macros. Please anyone help me to understand these.
These macros are defined in linux/serio.h... (2 Replies)
can some one please tell the meaning of the second statement i.e
n=${m#*=}
i couldnt get the meaning of the #*=
1.) m="mohit=/c/main/issue"
echo $m
result
-----------
mohit=/c/main/issue
2.) n=${m#*=}
echo $n
RESULT
-------
/c/main/issue (1 Reply)
Hi ,
Can anyone please let me know whta the follwoing piece of code for
ScriptName=${0##*/}
if pgrep -f "$ScriptName" | grep -v "^$$\$" ; then
echo `date`": Sctipt $ScritName is already runnig"
exit
fi
Thnx a lot in advance
Please use code tags when posting data and code... (8 Replies)
Please let me know the meaning for the below statements in shell scripting.
1) exit -99
--------------------------------
2) set prgdir = `pwd`
set runFlag = runFlag:FALSE
-------------------------------------
3) if (-f $prgdir/maillst.eml) then
set distEmail = `cat $prgdir/maillst.eml`... (1 Reply)
Hello everyone,
I'm looking for the meaning of this expression, as I don't understand it quite clearly : $1^
What do you think it could be?
I thought either:
- match lines starting with argument 1 but it should be ^$1
- turn line around : word becomes drow
Thanks in advance for your... (4 Replies)
Discussion started by: bibelo
4 Replies
LEARN ABOUT DEBIAN
surfraw-update-path
SURFRAW-UPDATE-PATH(1) User Contributed Perl Documentation SURFRAW-UPDATE-PATH(1)NAME
surfraw-update-path - updates PATH in shell config files
SYNOPSIS
surfraw-update-path [-add] [-remove] [-check] [-sys] [-all] [-help] [-shell=SHELL]
DESCRIPTION
surfraw-update-path adds the surfraw elvi directory (/usr/lib/surfraw) to your PATH in your shell's config file.
Currently it supports bash, sh, csh, tcsh, ash, dash, ksh, pdksh, zsh, rc, and es
Don't forget to login again or source your login files for it to take effect.
OPTIONS -check
Checks to see if the surfraw config code is present. This is the default.
-add
Adds the surfraw config code.
-remove
Removes the surfraw config code
-sys
Updates the system-wide shell config instead of the user. Must be done as root.
-shell=SHELL
Selects the shell to configure. Defaults to the value of the $SHELL environment variable.
Currently supported shells are:
sh, ash, bash, dash, csh, tcsh, ksh, pdksh, zsh, rc, and es.
-all
Attempts to configure the startup files for all known shells
-help
Gives a usage message
RETURN VALUE -check returns 0 if the surfraw code is present in the file, 1 if it is not found, or 2 on error.
All other options return 0 on success, or 2 on error.
ENVIRONMENT
SHELL
Used to determine which shell to configure, if -shell is not given.
HOME
Used to find users config files.
ENV Used by posix-compliant shells to specify a startup rc file.
ZDOTDIR
Used to find user config files for zsh. If not set, defaults to HOME.
SEE ALSO surfraw(1), sh(1), ash(1), bash(1), dash(1), csh(1), tcsh(1), ksh(1), pdksh(1), zsh(1), rc(1), es(1)AUTHOR
Ian Beckwith <ianb@erislabs.net>
perl v5.12.4 2011-07-12 SURFRAW-UPDATE-PATH(1)