while (*s++ = ((*t & 0x60) == 0x40 ? *t ^ 0x20 : *t)) t++;

[Jonas Hammarberg]

Copying string, turning upper case into lower case...

[hdjim]

increment the address of s set the value of s to the value of t and increment t. the value of t is dependent on the if statement. AND the value of t with 0x60 and if bit 6 is set, make the value of s = the value of t exclusive ored with 32,otherwise set s to the value of t... then increment the address of t. do this until the value of s is not true.

modified on Monday, August 30, 2010 9:33 AM

[ehoagland66]

I used to write my code like this until my boss beat me with stick and took my coffee cup :laugh:

[philcaetano]

Trying to figure this out, will causes someone to lose more productive than the multi-monitor/multi-tasking debate. ;P

[Andreas Mertens]

I remember using this technique for an assembly program I wrote many years ago. When I worked out what it was doing, it took a moment to realize why it look familiar... Andreas Mertens

[Larry G Grimes]

It definitely returns a string with all lowercase characters.

[M i s t e r L i s t e r]

wastes a lot of peoples time on this site ?

[tom1443]

This looks like an job interview question, in which case I don't want the job.

[PHLIPH]

Yeah, converts to lower case is right - but don't forget it also does '@' => '`', '[' => '{', '\' => '|', ']' => '}', '^' => '-', and '_' => del. Just felt the need to punctuate it. :)

[neil hudson]

It corrupts strings with @ [ \ ] ^ and _ in them.

Neil Hudson

[Rosenne]

Only in America... I mean, only for US ASCII. :thumbsdown:

[yoni at jefco]

I was going to say "Hopefully get someone sacked". Maybe a bit harsh on my part.

[Matthew Barnett]

Larry G. Grimes wrote:

It definitely returns a string with all lowercase characters.

It'll change other characters too, such as '@' to '`'!

[Jonas Hammarberg]

Worked for ANSI to, albeit only the lower parts :rolleyes:

[Lev Vayner]

maybe the author should start writing normal code.. in c#, this would be done with s.ToLower() yeah.. thats it.. no non-sense pointer code with an inline loop referencing hex values

[Rosenne]

I the context of software, only as well as but generally mean a bug.

[stevee1984]

Maybe something like this would work better, then we can use the code for email addresses etc. while (*s++ = (*t >='A' && *t <= 'Z' ? *t ^ 0x20 : *t) ) t++;

[DominLondon]

Robbo!

[Rob Philpott]

Dude!

Regards, Rob Philpott.

[leonej_dt]

I will assume both s and t are char*. *t & 0x60: Filters all but two bits of *t. I will call those bits xy (the most significant one first). (*t & 0x60) == 0x40: Tests whether xy is 10. (*t & 0x60) == 0x40 ? *t ^0x20 : *t: If xy is 10, it returns a new character equal to *t, but with xy equal to 11. Otherwise, it returns the original character. The whole loop iterates through a C string starting at s and copies it to another C string starting at t, but characters from 0x40 to 0x5F are converted into characters from 0x60 to 07F. The original string is left untouched, unless s equals t. (If t points to another character actually inside the C string pointed by s or vice versa, the program goes crazy.) To the end user, this means the following: Uppercase characters are converted into lowercase characters, square brackets are converted into braces, the backslash is converted into a vertical line character, the French circumflex accent character is converted into the tilde character, and the underline character is converted into a DEL character.

If you can play The Dance of Eternity (Dream Theater), then we shall make a band.