4.7.1 Translating Path Name Formats

4.7.1  Translating Path Name Formats

 split takes two arguments: a pattern and a string. It breaks up the string into one or more substrings based on the pattern. The call to split returns all the substrings in the original sequence.

Suppose we have a file name with path in the Unix style. Assume we want to convert it into the Microsoft Windows style. In the Unix style, directory and file names are separated by /. Therefore, a valid name is something like the following.

/users/server/faculty/kalita/public_html/index.html

The same name in the Microsoft Windows style looks like

\users\server\faculty\kalita\public_html\index.html

There are many ways to do this conversion. One way is given below. Note that this is not the most efficient way to do so.

 Program 4.23

#!/usr/bin/perl

print join ("\\", split (m@/@, $ARGV[0])), "\n";

Assuming the script is stored in the file convert.pl, a call to this script is something like 

%convert.pl /users/server/faculty/kalita/public_html/index.html

It prints the name in the Microsoft Windows style.

\users\server\faculty\kalita\public_html\index.html

First, split takes the argument given to it and produces a list whose elements are 

"users" "server" "faculty" "kalita" "public_html" "index.html"

Next, the join operator takes a string of length zero or more (not a pattern) and uses this string as the glue to put the list (the second argument) together. In this case, putting the list back together with \ as the glue or the separator gives us the file name in the Microsoft style. The backslash needs to be escaped using another backslash inside a string.