error when import zlib in iphone sdk

I have included in my iphone application and the source code I was mocking up the sample code of Molecules provided by Brad Larson, however, when I build the project, it returns the error as below. Can anyone point out for me whether this is a library linking problem or am I missing something else?

"_deflate", referenced from: -[NSData(Gzip) gzipDeflate] in NSData+Gzip.o "_inflateEnd", 
referenced from: -[NSData(Gzip) initWithGzippedData:] in NSData+Gzip.o "inflateInit2", 
referenced from: -[NSData(Gzip) initWithGzippedData:] in NSData+Gzip.o "_inflate", 
referenced from: -[NSData(Gzip) initWithGzippedData:] in NSData+Gzip.o "_deflateEnd", 
referenced from: -[NSData(Gzip) gzipDeflate] in NSData+Gzip.o "deflateInit2", referenced 
from: -[NSData(Gzip) gzipDeflate] in NSData+Gzip.o ld: symbol(s) not found collect2: ld 
returned 1 exit status

From stackoverflow

• In your Target settings window, scroll down to the "Other Linker Flags" section and make sure that -lz is in the field. This will link against the built-in zlib, and your error should go away.

  issac : yeah it solve the problem thanks

• Add libz to your project. To do this, follow these steps in Xcode:

  1. Open your project, select your project target and then click the blue project info icon on your toolbar (or press ⌘I)
     
  2. Click the + button in the lower-left corner of the screen to add a library, scroll down to the bottom of the library list and select libz.dylib; click the Add button.
     
  3. Once you've clicked add, you will see that the library name appears in oyur list of Linked Libraries. You will now be able to build your project without linking errors.
     

  You can use this same method to add any library from the list. If the library does not appear on the list, then you know that it is not part of the standard iPhone SDK and you may need to rethink your solution or build the library statically yourself and link your target to that (if even possible).

• thanks everybody it works perfectly

• Hi,

  Can anyone help me in knowing, what actually the molecules code do, of one of the following..

  a) Does it download the gzip fie using iphone sdk and then uncompress it using zlib. b) or Does it directly download the buffer and utilise it

  I have gone through the code, but I didnt got much clear Idea. Please help.

  bentford : Try asking a new question--the answers area is not for comments or answers.

• WOW!! I can't believe I wasted around 2 hours trying to figure out why my libraries wouldn't link. You saved my life. I'm eternally grateful to you. :D :D :D

  bentford : Anything that's not an answer should go in the comments area like this.

• thank you very much Its cleared 8 errors to my project .......

  bentford : The answers area is not for comments.