[root@HK81-107 postgresql-9.0.0]# ./configure  
checking build system type... i686-pc-linux-gnu  
checking host system type... i686-pc-linux-gnu  
checking which template to use... linux  
checking whether to build with 64-bit integer date/time support... yes  
checking whether NLS is wanted... no  
checking for default port number... 5432  
checking for block size... 8kB  
checking for segment size... 1GB  
checking for WAL block size... 8kB  
checking for WAL segment size... 16MB  
checking for gcc... gcc  
checking for C compiler default output file name... a.out  
checking whether the C compiler works... yes  
checking whether we are cross compiling... no  
checking for suffix of executables...  
checking for suffix of object files... o  
checking whether we are using the GNU C compiler... yes  
checking whether gcc accepts -g... yes  
checking for gcc option to accept ISO C89... none needed  
checking if gcc supports -Wdeclaration-after-statement... yes  
checking if gcc supports -Wendif-labels... yes  
checking if gcc supports -fno-strict-aliasing... yes  
checking if gcc supports -fwrapv... yes  
checking whether the C compiler still works... yes  
checking how to run the C preprocessor... gcc -E  
checking allow thread-safe client libraries... yes  
checking whether to build with Tcl... no  
checking whether to build Perl modules... no  
checking whether to build Python modules... no  
checking whether to build with GSSAPI support... no  
checking whether to build with Kerberos 5 support... no  
checking whether to build with PAM support... no  
checking whether to build with LDAP support... no  
checking whether to build with Bonjour support... no  
checking whether to build with OpenSSL support... no  
checking for grep that handles long lines and -e... /bin/grep  
checking for egrep... /bin/grep -E  
checking for ld used by GCC... /usr/bin/ld  
checking if the linker (/usr/bin/ld) is GNU ld... yes  
checking for ranlib... ranlib  
checking for strip... strip  
checking whether it is possible to strip libraries... yes  
checking for ar... ar  
checking for tar... /bin/tar  
checking whether ln -s works... yes  
checking for gawk... gawk  
checking for a thread-safe mkdir -p... /bin/mkdir -p  
checking for bison... no  
configure: WARNING:  
* Without Bison you will not be able to build PostgreSQL from CVS nor  
* change any of the parser definition files. You can obtain Bison from  
* a GNU mirror site. (If you are using the official distribution of  
* PostgreSQL then you do not need to worry about this, because the Bison  
* output is pre-generated.)  
checking for flex... no  
configure: WARNING:  
* Without Flex you will not be able to build PostgreSQL from CVS nor  
* change any of the scanner definition files. You can obtain Flex from  
* a GNU mirror site. (If you are using the official distribution of  
* PostgreSQL then you do not need to worry about this because the Flex  
* output is pre-generated.)  
checking for perl... /usr/bin/perl  
configure: using perl 5.8.8  
checking for main in -lm... yes  
checking for library containing setproctitle... no  
checking for library containing dlopen... -ldl  
checking for library containing socket... none required  
checking for library containing shl_load... no  
checking for library containing getopt_long... none required  
checking for library containing crypt... -lcrypt  
checking for library containing fdatasync... none required  
checking for library containing gethostbyname_r... none required  
checking for library containing shmget... none required  
checking for -lreadline... no  
checking for -ledit... no  
configure: error: readline library not found  
If you have readline already installed, see config.log for details on the  
failure. It is possible the compiler isnt looking in the proper directory.  
Use --without-readline to disable readline support.