strrot13 - encrypt or decrypt string using rot13
#include <publib.h>
char *strrot13(char *str);
strrot13 converts the argument string using rot13, i.e., it replaces each
letter a with n, n with a, b with o, o with b, and so on. Converting twice
results in the original string. Non-letter characters are not converted.
The rot13 encryption method is used commonly on USENET to hide
offensive text, or spoilers in discussions about movies or books, or in
other similar occasions.
strrot13 returns its argument.
Lars Wirzenius (lars.wirzenius@helsinki.fi)