Workshop

Workshop

Quiz

1:	To have data generated by your program display a page at a time, use perl myprog.pl | more open(M, "| more") || die; print M "data...data...data....\n"; open(M, ">more") || die; print M "data..data...data...\n";
2:	Which value of $foo is used in this statement: $r=`dir $foo`? The shell's value for $foo. Perl's value of $foo is substituted, and then the dir is run.
3:	Which of the following tasks changes depending on what system you have? Finding the amount of free disk space Getting a directory listing Deleting a directory

Answers

A1:	Either a or b. In the case of a, all output of myprog.pl is fed to more. In the case of b, any data written to the M file descriptor is fed to more for paging.
A2:	b. To protect $foo from Perl's expansion, you use qx`dir $foo`.
A3:	a only. Choice b can be done with glob, <*> or opendir and readdir, and c is done with rmdir.

Activities

• Use the statistics functions in Hour 8, "Functions," to display even more statistics about the sizes of files in Listing 11.1.

• If you have a Unix system, add your particular flavor of Unix to the freespace() function. Use the Linux example as a starting point.