Installing libpng version 1.0.9 - January 31, 2001Before installing libpng, you must first install zlib.  zlibcan usually be found wherever you got libpng.  zlib can beplaced in another directory, at the same level as libpng.Note that your system might already have a preinstalledzlib, but you will still need to have access to thezlib.h and zconf.h include files that correspond to theversion of zlib that's installed.You can rename the directories that you downloaded (theymight be called "libpng-1.0.9" or "lpng109" and "zlib-1.1.3"or "zlib113") so that you have directories called "zlib" and "libpng".Your directory structure should look like this:   ..       (the parent directory)      libpng  (this directory)          INSTALL (this file)          README          *.h          *.c          contrib             gregbook             msvctest             pngminus             pngsuite             visupng          projects             borland             msvc             wince          scripts             makefile.*          pngtest.png          etc.      zlib          README          *.h          *.c          contrib          etc.If the line endings in the files look funny, you may wish to get the otherdistribution of libpng.  It is available in both tar.gz (UNIX style lineendings) and zip (DOS style line endings) formats.If you are building libpng with MSVC, you can enter the libpng\msvc directoryand follow the instructions in msvc\README.txt.  You can build libpng forWindowsCE by entering the libpng\wince directory and following theinstructions in the README* files.Else enter the zlib directory and follow the instructions in zlib/README,then come back here and choose the appropriate makefile.sys in the scriptsdirectory.The files that are presently available in the scripts directoryinclude makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a) makefile.linux    =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.0.9) makefile.gcmmx    =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.0.9,                       uses assembler code tuned for Intel MMX platform) makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a) makefile.knr      =>  Archaic UNIX Makefile that converts files with                       ansi2knr (Requires ansi2knr.c from                       ftp://ftp.cs.wisc.edu/ghost) makefile.aix      =>  AIX makefile makefile.cygwin   =>  Cygwin/gcc makefile makefile.dec      =>  DEC Alpha UNIX makefile makefile.hpux     =>  HPUX (10.20 and 11.00) makefile makefile.ibmc     =>  IBM C/C++ version 3.x for Win32 and OS/2 (static) makefile.intel    =>  Intel C/C++ version 4.0 and later libpng.icc        =>  Project file for IBM VisualAge/C++ version 4.0 or later makefile.macosx   =>  MACOS X Makefile makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib) makefile.sggcc    =>  Silicon Graphics (gcc, creates libpng.so.2.1.0.9) makefile.sunos    =>  Sun makefile makefile.solaris  =>  Solaris 2.X makefile (gcc, creates libpng.so.2.1.0.9) makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc makefile.mips     =>  MIPS makefile makefile.acorn    =>  Acorn makefile makefile.amiga    =>  Amiga makefile smakefile.ppc     =>  AMIGA smakefile for SAS C V6.58/7.00 PPC compiler                       (Requires SCOPTIONS, copied from scripts/SCOPTIONS.ppc) makefile.atari    =>  Atari makefile makefile.beos     =>  BEOS makefile for X86 makefile.bor      =>  Borland makefile (uses bcc) makefile.bc32     =>  32-bit Borland C++ (all modules compiled in C mode) makefile.bd32     =>  To make a png32bd.dll with Borland C++ 4.5 makefile.tc3      =>  Turbo C 3.0 makefile makefile.dj2      =>  DJGPP 2 makefile makefile.msc      =>  Microsoft C makefile makefile.vcawin32 =>  makefile for Microsoft Visual C++ 5.0 and later (uses                       assembler code tuned for Intel MMX platform) makefile.vcwin32  =>  makefile for Microsoft Visual C++ 4.0 and later (does                       not use assembler code) makefile.os2      =>  OS/2 Makefile (gcc and emx, requires pngos2.def) pngos2.def        =>  OS/2 module definition file used by makefile.os2 makefile.watcom   =>  Watcom 10a+ Makefile, 32-bit flat memory model makevms.com       =>  VMS build script descrip.mms       =>  VMS makefile for MMS or MMK pngdef.pas        =>  Defines for a png32bd.dll with Borland C++ 4.5 SCOPTIONS.ppc     =>  Used with smakefile.ppcCopy the file (or files) that you need from thescripts directory into this directory, for example   MSDOS example: copy scripts\makefile.msc makefile   UNIX example:    cp scripts/makefile.std makefileRead the makefile to see if you need to change any source ortarget directories to match your preferences.Then read pngconf.h to see if you want to make any configurationchanges.Then just run "make test" which will create the libpng library inthis directory and run a quick test that reads the "pngtest.png"file and writes a "pngout.png" file that should be identical to it.Look for "9782 zero samples" in the output of the test.  For moreconfidence, you can run another test by typing "pngtest pngnow.png"and looking for "289 zero samples" in the output.  Also, you canrun "pngtest -m *.png" in the "contrib/pngsuite" directory and compareyour output with the result shown in contrib/pngsuite/README.Most of the makefiles will allow you to run "make install" toput the library in its final resting place (if you want todo that, run "make install" in the zlib directory first if necessary).Further information can be found in the README and libpng.txtfiles, in the individual makefiles, in png.h, in the README files insubdirectories of the LIB directory, and the manual pages libpng.3 and png.5.