Coverage (of exam, too!):

Perl
C review topics: pointers C6 & C8

As usual, it's critical that no program crashes. You'll get more credit for a program that does nothing or gives incorrect results than for one that has a syntax or logical error that causes the grading script to crash! This includes making sure that your C programs compile and run correctly on the department Solaris systems. Don't submit the executables for them; we'll compile them. And, speaking of C, figure that the exam will include problems that are strongly related to the ones on this lab.

And now, speaking of the exam, the Perl part of it will be related to the Perl programs we'll have covered in class.

Choose three of these seven programs from Lab 2: backup, oneword, nodigits, moredips, Asiapop.awk, avgpop.awk and chem.awk, and write Perl versions of them.

• Give them the same names, but with pl extensions. E.g., backup.pl, oneword.pl, etc. In the case of the awk scripts, replace awk by pl: e.g, Asiapop.pl.
• The first four should behave the same way on this lab as on the earlier one. The last three will not take any argument: they should open the data file /mnt/usr/DATA/world within the script.
• The first line in these programs, of course, should either be

  #! /usr/bin/perl -w
  

  or

  #! /opt/local/bin/perl -w
  

  (don't worry about which one to choose).
• Part of the grade will be allocated on how well your comments (use #, as in the Bourne shell) help illuminate your code.

pointersstuff) Assume the definitions

struct {
	char name[50];	// null-terminated
	char ssn[10];	// ditto
	int class	// 1 for freshman/woman; 2 for sophomore; etc.
	float balance_on_bill;
} student, *sptr, classlist[200];

• the balance on student's bill (not printing it or anything, just an expression for it)
• the class of sptr's object (ditto)
• the last digit of student's ssn (here too)
• printing (yes: this time, print the expression) to stdout the name of the very first student of classlist: printf(
• reading from stdin the balance on student's bill: scanf(

lastarglength.c) This is (obviously) a C program. It returns the length of the last command-line argument. We'll call its executable lastarglength. Hence

$ lastarglength of mine
The length of the last command-line argument is 4.
$ lastarglength
The length of the last command-line argument is 13.