UNIX head command not working? Post: 302928813

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Homework and Emergencies Homework & Coursework Questions UNIX head command not working? Post 302928813 by lukefrost96 on Monday 15th of December 2014 11:58:17 AM

12-15-2014

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UNIX head command not working?

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1. The problem statement, all variables and given/known data:

Write a script that allows the user to print the first n lines or the last n lines of every file in the directory specified by the argument. e.g. lshead -head 2 Documents will print the first two lines of every file in the documents directory.

2. Relevant commands, code, scripts, algorithms:

Head command is used in this command as well as the tail command.

3. The attempts at a solution (include all code and scripts):

Code:

if [ $# -lt 0 ];
then
    echo "A directory name as an argument is expected"
    exit 1
fi

if [ $2 -lt 0 ];
then
        echo "expected a positive integer"
        exit 1
fi

if [ $1 = "-head" ];
then
    head -n $3

elif [ $1 "-tail" ];
then
    tail -n $3
else
         echo "Enter either head or tail"
         exit 1
fi
exit 0

I have run it and it comes up with this error:
head: Documents: invalid number of lines

I don't understand why it isn't working, I have even consulted friends on this and even they can't understand why it isn't working.

4. Complete Name of School (University), City (State), Country, Name of Professor, and Course Number (Link to Course):
University of Huddersfield, Huddersfield, United Kingdom, Dr Gary Allen, CFT2112

Note: Without school/professor/course information, you will be banned if you post here! You must complete the entire template (not just parts of it).

lukefrost96

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LEARN ABOUT REDHAT

head

HEAD(1) 								FSF								   HEAD(1)

NAME

       head - output the first part of files

SYNOPSIS

       head [OPTION]... [FILE]...

DESCRIPTION

       Print  first  10 lines of each FILE to standard output.	With more than one FILE, precede each with a header giving the file name.  With no
       FILE, or when FILE is -, read standard input.

       Mandatory arguments to long options are mandatory for short options too.

       -c, --bytes=SIZE
	      print first SIZE bytes

       -n, --lines=NUMBER
	      print first NUMBER lines instead of first 10

       -q, --quiet, --silent
	      never print headers giving file names

       -v, --verbose
	      always print headers giving file names

       --help display this help and exit

       --version
	      output version information and exit

       SIZE may have a multiplier suffix: b for 512, k for 1K, m for 1 Meg.

AUTHOR

       Written by David MacKenzie.

REPORTING BUGS

       Report bugs to <bug-coreutils@gnu.org>.

COPYRIGHT

       Copyright (C) 2002 Free Software Foundation, Inc.
       This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
       LAR PURPOSE.

SEE ALSO

       The  full documentation for head is maintained as a Texinfo manual.  If the info and head programs are properly installed at your site, the
       command

	      info head

       should give you access to the complete manual.

head (coreutils) 4.5.3						   February 2003							   HEAD(1)