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 MINIX

make

MAKE(1) 						      General Commands Manual							   MAKE(1)

NAME

       make - a program for maintaining large programs

SYNOPSIS

       make [-f file] [-iknpqrst] [option] ... [target]

OPTIONS

       -f     Use file as the makefile

       -i     Ignore status returned by commands

       -k     On error, skip to next command

       -n     Report, but do not execute

       -p     Print macros and targets

       -q     Question up-to-dateness of target

       -r     Rule inhibit; do not use default rules

       -s     Silent mode

       -t     Touch files instead of making them

EXAMPLES

       make kernel	   # Make kernel up to date

       make -n -f mfile    # Tell what needs to be done

DESCRIPTION

       Make  is  a program that is normally used for developing large programs consisting of multiple files.  It keeps track of which object files
       depend on which source and header files.  When called, it does the minimum amount of recompilation to bring the target file up to date.

       The file dependencies are expected in makefile or Makefile , unless another file is specified with -f.  Make has some default  rules  built
       in, for example, it knows how to make .s files from .c files.  Here is a sample makefile .

	 d=/user/ast		     # d is a macro
	 program:		     head.s tail.s# program depends on these
		 cc -o program head.s tail.s# tells how to make program
		 echo Program done.  # announce completion
	 head.s: $d/def.h head.c     # head.s depends on these
	 tail.s: $d/var.h tail.c     # tail.s depends on these

       A  complete  description of make would require too much space here.  Many books on UNIX discuss make .  Study the numerous Makefiles in the
       MINIX source tree for examples.

SEE ALSO

       cc(1).

																	   MAKE(1)