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Full Discussion: Extract a line from a file using the line number
Top Forums Shell Programming and Scripting Extract a line from a file using the line number Post 302191094 by zambo on Thursday 1st of May 2008 01:19:00 PM
Old 05-01-2008
Extract a line from a file using the line number
I have a shell script and want to assign a value to a variable. The value is the line exctrated from a file using the line number. The line number it is not fix, and could change any time.
I have tried sed, awk, head .. See my script

# Get randome line number from the file
#selectedline = `awk 'NR==$randomline {print $0}' $filename`
#awk 'NR==$randomline {print $0}' $filename
selectedline=`sed -n "${randomline}{p;q;}" $filename`
#sed -n "${randomline}{p;q;}" $filename
#selectedline=`head -$randomline $filename |tail -1`
#head -${randomline} $filename |tail -1
echo "Random line = $selectedline"
The problem is that after getting the desired line specified by randomline, the entire file is expanded in the variable selectedline. This the case only ,when assigned to a variable.

Need help
 

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LEARN ABOUT SUNOS

yppasswdd

yppasswdd(4)							   File Formats 						      yppasswdd(4)

NAME

       yppasswdd - configuration file for rpc.yppasswdd (NIS password daemon)

SYNOPSIS

       /etc/default/yppasswdd

DESCRIPTION

       The yppasswdd file contains a parameter that modifies the behavior of the rpc.yppasswdd(1M) daemon.

       The yppasswdd file contains a single parameter:

       #check_restricted_shell_name=1

       By  default in the current release, this line in yppasswdd is commented	out. If you uncomment the line, when a user attempts to change his
       default shell using `passwd -r nis -e` (see passwd(1)),	the rpc.yppasswdd daemon checks whether the  name  of  the  user's  current  shell
       begins  with  an  'r'.  rpc.yppasswdd considers any  shell whose name begins with an 'r' (for example, rcsh) to be a restricted shell. If a
       user's shell does begin with 'r', his attempt to change from the default shell will fail.

       If the line in the yppasswdd file is commented out (the default), the rpc.yppasswdd daemon does not perform the restricted shell check.

       The yppasswdd file is editable only by root or a member of the sys group.

FILES

       /etc/default/yppasswdd	       configuration file for rpc.yppasswdd daemon

SEE ALSO

       rpc.yppasswdd(1M)

SunOS 5.10							    8 Nov 2001							      yppasswdd(4)
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