strfry - phpMan

File: libc.info,  Node: strfry,  Next: Trivial Encryption,  Prev: Finding Tokens in a String,  Up: String and Array Utilities
5.9 strfry
==========
The function below addresses the perennial programming quandary: "How do
I take good data in string form and painlessly turn it into garbage?"
This is actually a fairly simple task for C programmers who do not use
the GNU C Library string functions, but for programs based on the GNU C
Library, the 'strfry' function is the preferred method for destroying
string data.
   The prototype for this function is in 'string.h'.
 -- Function: char * strfry (char *STRING)
     Preliminary: | MT-Safe | AS-Safe | AC-Safe | *Note POSIX Safety
     Concepts::.
     'strfry' creates a pseudorandom anagram of a string, replacing the
     input with the anagram in place.  For each position in the string,
     'strfry' swaps it with a position in the string selected at random
     (from a uniform distribution).  The two positions may be the same.
     The return value of 'strfry' is always STRING.
     *Portability Note:* This function is unique to the GNU C Library.