LinuxQuestions.org
Help answer threads with 0 replies.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie
User Name
Password
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!

Notices


Reply
  Search this Thread
Old 02-16-2012, 10:23 PM   #1
Jon Blanchard
LQ Newbie
 
Registered: Feb 2012
Location: Franklin, TN
Distribution: Linux, AIX
Posts: 6

Rep: Reputation: Disabled
The single period before a command or shell script filename


Consider the following line from a .profile script:
Code:
if [ -r .profile.local.start ] ; then . .profile.local.start ; fi
                                      ^
How is that single period interpreted, referenced by the caret underneath it? If I am going to run the .profile file in a cron job, do I use the following form?
Code:
00 21 * * * /home/hci/.profile; /home/hci/getstats2.sh
...or does the crontab line need to be the following?
Code:
00 21 * * * . /home/hci/.profile; /home/hci/getstats2.sh
Should I enclose all commands in parens?
Code:
00 21 * * * (. /home/hci/.profile; /home/hci/getstats2.sh)
Thanks in advance for your response.
 
Old 02-16-2012, 10:59 PM   #2
chrism01
LQ Guru
 
Registered: Aug 2004
Location: Sydney
Distribution: Rocky 9.2
Posts: 18,356

Rep: Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751Reputation: 2751
the
Code:
.<space>filename>
convention is equiv to the 'source' cmd, which embeds the named file content (usually env settings ala .rpofile) into the current shell env, instead of creating a subshell (which is what happens when you call a shell file).
See http://linux.die.net/man/1/bash & search for 'source'
Quote:
. filename [arguments]
source filename [arguments]
Read and execute commands from filename in the current shell environment and return the exit status of the last command executed from filename. If filename does not contain a slash, file names in PATH are used to find the directory containing filename. The file searched for in PATH need not be executable. When bash is not in posix mode, the current directory is searched if no file is found in PATH. If the sourcepath option to the shopt builtin command is turned off, the PATH is not searched. If any arguments are supplied, they become the positional parameters when filename is executed. Otherwise the positional parameters are unchanged. The return status is the status of the last command exited within the script (0 if no commands are executed), and false if filename is not found or cannot be read.
HTH

See also
http://rute.2038bug.com/index.html.gz
http://tldp.org/LDP/Bash-Beginners-G...tml/index.html
http://www.tldp.org/LDP/abs/html/

As far as cron goes, best to just call a simple cmd eg the shell script and then source or .<space> inside the shell script at the top

Last edited by chrism01; 02-16-2012 at 11:00 PM.
 
  


Reply

Tags
cronjob, period



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
mp3 filename to xml shell script jason7 Linux - Server 1 03-21-2009 05:22 AM
Shell script for changing filename case Steve W Linux - Software 8 10-17-2008 03:15 AM
single command in shell script not working farkus888 Programming 5 04-01-2008 01:31 PM
shell script/command for converting columns/table onto a single line skuz_ball Programming 9 11-30-2007 03:02 AM
shell script:filename containing space ! Dr_Death_UAE Programming 3 12-16-2006 06:46 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 06:39 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration