>make testfile
cc    -o testfile testfile.c
"testfile.c", line 117: warning: no explicit type given
"testfile.c", line 119: warning: no explicit type given
"testfile.c", line 121: warning: no explicit type given
"testfile.c", line 122: warning: no explicit type given
"testfile.c", line 123: warning: no explicit type given
Undefined                       first referenced
 symbol                             in file
sqlcxt                              testfile.o
ld: fatal: Symbol referencing errors. No output written to testfile
*** Error code 1
make: Fatal error: Command failed for target `testfile'

/* SQLLIB Prototypes */
extern sqlcxt (/*_ void **, unsigned int *,
                   struct sqlexd *, struct sqlcxp * _*/);
extern sqlcx2t(/*_ void **, unsigned int *,
                   struct sqlexd *, struct sqlcxp * _*/);
extern sqlbuft(/*_ void **, char * _*/);
extern sqlgs2t(/*_ void **, char * _*/);
extern sqlorat(/*_ void **, unsigned int *, void * _*/);

C:\>proc

Pro*C/C++: Release 10.2.0.4.0 - Production on Fri Mar 26 09:37:38 2010

Copyright (c) 1982, 2007, Oracle.  All rights reserved.

System default option values taken from: C:\oracle\ora102\precomp\admin\pcscfg.cfg

Option Name    Current Value  Description
-------------------------------------------------------------------------------
auto_connect   no             Allow automatic connection to ops$ account
char_map       charz          Mapping of character arrays and strings
close_on_commitno             Close all cursors on COMMIT
cmax           100            CMAX Value for connection pool
cmin           2              CMIN Value for connection pool
cincr          1              CINCR Value for connection pool
ctimeout       0              CTIMEOUT Value for connection pool
cnowait        0              CNOWAIT Value for connection pool

comp_charset   multi_byte     The character set type the C compiler supports
config         default        Override system configuration file with another
cpool          no             Support connection pooling
cpp_suffix     *none*         Override the default C++ filename suffix
dbms           native         v6/v7/v8 compatibility mode
def_sqlcode    no             Generate '#define SQLCODE sqlca.sqlcode' macro
define         WIN32_LEAN_AND_Define a preprocessor symbol
duration       transaction    Set pin duration for objects in the cache
dynamic        oracle         Specify Oracle or ANSI Dynamic SQL Semantics
errors         yes            Whether error messages are sent to the terminal
errtype        *none*         Name of the list file for intype file errors
events         no             Support publish-subscribe event notifications
fips           none           FIPS flagging of ANSI noncompliant usage
header         *none*         Specify file extension for Precompiled Headers
hold_cursor    no             Control holding of cursors in the cursor cache
iname          *none*         The name of the input file
include        *none*         Directory paths for included files
intype         *none*         The name of the input file for type information
lines          no             Add #line directives to the generated code
lname          *none*         Override default list file name
ltype          none           The amount of data generated in the list file
maxliteral     1024           Maximum length of a generated string literal
maxopencursors 10             Maximum number of cached open cursors
mode           oracle         Code conformance to Oracle or ANSI rules
native_types   no             Support for native float/double
nls_char       *none*         Specify National Language character variables
nls_local      no             Control how NLS character semantics are done
objects        yes            Support object types
oname          *none*         The name of the output file
oraca          no             Control the use of the ORACA
pagelen        80             The page length of the list file
parse          none           Control which non-SQL code is parsed
prefetch       1              Number of rows pre-fetched at cursor OPEN time
release_cursor no             Control release of cursors from cursor cache
select_error   yes            Control flagging of select errors
sqlcheck       syntax         Amount of compile-time SQL checking
sys_include    *none*         Directory where system header files are found
threads        no             Indicates a multi-threaded application
type_code      oracle         Use Oracle or ANSI type codes for Dynamic SQL
unsafe_null    no             Allow a NULL fetch without indicator variable
userid         *none*         A username/password [@dbname] connect string
utf16_charset  nchar_charset  The character set form used by UTF16 variables
varchar        no             Allow the use of implicit varchar structures
version        recent         Which version of an object is to be returned
win32_threads  no             Support windows default local threading
PCC-F-02135, CMD-LINE:  User asked for help