CS
332/532
–
1G-
Systems
Programming
HW
2

Objectives

To
implement
a



search



program
in
C
program
using
system
calls
for
files
and
directories.

Description

Find
is
a
popular
UNIX
command
that
traverses
a
file
hierarchy
and
performs
various
functions
on
each
file
in
the
hierarchy.
The
goal
of
this
project
is
to
implement
a
program
similar
called



search



that
supports
the
following
functionality:

1.


The
program
should
take
the
directory
name
from
where
to
start
the
file
traversal
as
a
command-line
argument
and
print
the
file
hierarchy
starting
with
the
directory
that
is
provided
by
the
command-line
argument.

2.


If
the
program
is
executed
without
any
arguments,
the
program
should
print
the
file
hierarchy
starting
with
the
current
directory
where
the
program
is
executed.
If
there
are
no
directories
in the current
directory only files are
listed one per line.

3.


If
there
are
other
directories
in
the
current
directory
then
the
directory
name
is
first
displayed
on
a
separate
line
and
then
the
files
in
that
directory
are
listed
one-per-line
with
one-tab
indentation.

4.


If
a
file
is
a
symbolic
link
then
the
program
should
display
the
symbolic
link
name
and
in
parentheses
the
file
name the
link
points
to.

5.


The
program
should
also
support
three
command-line
options:

1.


-S

This should list all
files
in the
hierarchy and print the
size, permissions, and
last access
time next to the filename in parenthesis. Print 0
for the size of a directory.

2.


-s
<>
size
in
bytes>

This should list all files in the hierarchy with file size less than or equal to the value
specified.

3.


-f


<>


pattern>

This should
list
all
files
in
the
hierarchy that
satisfy
the
following
conditions:
1)
the
file

name contains the substring in the string pattern option,
AND 2) the depth of the file
relative
to
the
starting
directory
of
the
traversal
is
less
than
or
equal
to
the
depth
option.
The
starting
directory
itself
has
a
depth
of
0.

6.


The program should support not only each of these options separately but also any
combination
of
these
options.
For
example:
-S,
-s
1024,
-f
jpg
1,
-S
-s
1024,
-S
-f
jpg
2,
-s
1024
-f
jpg
2,
-S
-s
1024
-f
jpg
1,
-S
-f
jpg
2
-s
1024.

7.


If


both


-s


and


-f


options


are


specified


then


the


program


should


list


only
those
files
that
match
both
criteria.
The
order
of
the
options
should
not
matter.

8.


[

Graduate
Students
Only

]
The
program
should
support
a
fourth
command-line
option:

1.



-t
f



-
list
regular
files
only

2.



-t
d



-
list
directories
only

Guidelines
and
Hints

1.


The
program
must
use
function
pointers
similar
to
Figure
4.22
in
the
text
book
to
implement
the
functionality
described
above.
You
can
use
the
logic
and
structure
from
Figure
4.22
as
the
starting
point
to
implement
this
program
(make
sure
to
go
over
the
program
in
Figure
4.22
and
understand
all
the
steps
performed).
However,
please
note
that
your
final
program
must
compile
and
execute
without
any
dependencies
on
the
source
code
provided
by
the
text
book.
You
can
find
a
simple
example
on
how
to
use
function
pointers
in
the


funcptr.c


file

2.


You can use the


getopt


function to process the command-line options. See


man 3
getopt



for
more
details
and
an
example
on
how
to
use



getopt



function.

3.


You
should
use
a
Makefile
to
compile
and
build
this
project
and
make
sure
to
submit
the
Makefile
along with the
rest of the
source code.

4.


You should upload all the source code, Makefile, and a README.txt file to Canvas. Please
do
not upload any
object files or executable
files.

Program
Documentation
and
Testing

1.


Use
appropriate
names
for
variables
and
functions.

2.


Use
a
Makefile
to
compile
your
program.

3.


Include
meaningful
comments
to
indicate
various
operations
performed
by
the
program.

4.


Programs
must
include
the
following
header
information
within
comments:

5.


Test
your
program
with
the
sample
test
cases
provided
as
well
as
your
own
test
cases.

6.


You
can
include
any
comments
you
may
have
about
testing
in
the
README.txt
file.

Examples

Sample
Input
and
Output:

If
you
have
the
following
directory
structure
as
shown
by
the
output
of
"ls
-lR"
command:

Then
the
output
of
find
without
any
argument
should
look
like
this:

It
is
not
necessary
that
the
order
of
the
files
are
exactly
as
shown
above,
but
the
overall
structure
should
look
similar
to
the
output
shown
above.
You
can
use
the
following
tar
file
to
create
the
directory
structure:


projects.tar
.
Download
this
file
and
extract
the
file using the
command: