1、头文件

#include <fcgi_stdio.h>

2、while(FCGI_Accept()>=0)//这里进入循环，前台每请求一次fcgi服务，就循环一次

循环内处理：

char *query_string=getenv("QUERY_STRING");

3、从获得的query_string解析查询字段，进行兴许操作。

4、用printf返回处理结果给webserver，再由webserver将结果返回给client。

（这里的printf函数是在fcgi_stdio.h中又一次定义了的）

附：fcgi_stdio.h

/*

 * fcgi_stdio.h --

 *

 *      FastCGI-stdio compatibility package

 *

 *

 * Copyright (c) 1996 Open Market, Inc.

 *

 * See the file "LICENSE.TERMS" for information on usage and redistribution

 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.

 *

 * $Id: fcgi_stdio.h,v 1.5 2001/06/22 13:21:15 robs Exp $

 */

#ifndef _FCGI_STDIO

#define _FCGI_STDIO 1

#include <stdio.h>

#include <sys/types.h>

#include "fcgiapp.h"

#if defined (c_plusplus) || defined (__cplusplus)

extern "C" {

#endif

#ifndef DLLAPI

#ifdef _WIN32

#define DLLAPI __declspec(dllimport)

#else

#define DLLAPI

#endif

#endif

/*

 * Wrapper type for FILE

 */

typedef struct {

    FILE *stdio_stream;

    FCGX_Stream *fcgx_stream;

} FCGI_FILE;

/*

 * The four new functions and two new macros

 */

DLLAPI int FCGI_Accept(void);

DLLAPI void FCGI_Finish(void);

DLLAPI int FCGI_StartFilterData(void);

DLLAPI void FCGI_SetExitStatus(int status);

#define FCGI_ToFILE(fcgi_file) (fcgi_file->stdio_stream)

#define FCGI_ToFcgiStream(fcgi_file) (fcgi_file->fcgx_stream)

/*

 * Wrapper stdin, stdout, and stderr variables, set up by FCGI_Accept()

 */

DLLAPI extern   FCGI_FILE       _fcgi_sF[];

#define FCGI_stdin      (&_fcgi_sF[0])

#define FCGI_stdout     (&_fcgi_sF[1])

#define FCGI_stderr     (&_fcgi_sF[2])

/*

 * Wrapper function prototypes, grouped according to sections

 * of Harbison & Steele, "C: A Reference Manual," fourth edition,

 * Prentice-Hall, 1995.

 */

DLLAPI void FCGI_perror(const char *str);

DLLAPI FCGI_FILE *FCGI_fopen(const char *path, const char *mode);

DLLAPI int        FCGI_fclose(FCGI_FILE *fp);

DLLAPI int        FCGI_fflush(FCGI_FILE *fp);

DLLAPI FCGI_FILE *FCGI_freopen(const char *path, const char *mode, FCGI_FILE *fp);

DLLAPI int        FCGI_setvbuf(FCGI_FILE *fp, char *buf, int bufmode, size_t size);

DLLAPI void       FCGI_setbuf(FCGI_FILE *fp, char *buf);

DLLAPI int        FCGI_fseek(FCGI_FILE *fp, long offset, int whence);

DLLAPI int        FCGI_ftell(FCGI_FILE *fp);

DLLAPI void       FCGI_rewind(FCGI_FILE *fp);

#ifdef HAVE_FPOS

DLLAPI int        FCGI_fgetpos(FCGI_FILE *fp, fpos_t *pos);

DLLAPI int        FCGI_fsetpos(FCGI_FILE *fp, const fpos_t *pos);

#endif

DLLAPI int        FCGI_fgetc(FCGI_FILE *fp);

DLLAPI int        FCGI_getchar(void);

DLLAPI int        FCGI_ungetc(int c, FCGI_FILE *fp);

DLLAPI char      *FCGI_fgets(char *str, int size, FCGI_FILE *fp);

DLLAPI char      *FCGI_gets(char *str);

/*

 * Not yet implemented

 *

 * int        FCGI_fscanf(FCGI_FILE *fp, const char *format, ...);

 * int        FCGI_scanf(const char *format, ...);

 *

 */

DLLAPI int        FCGI_fputc(int c, FCGI_FILE *fp);

DLLAPI int        FCGI_putchar(int c);

DLLAPI int        FCGI_fputs(const char *str, FCGI_FILE *fp);

DLLAPI int        FCGI_puts(const char *str);

DLLAPI int        FCGI_fprintf(FCGI_FILE *fp, const char *format, ...);

DLLAPI int        FCGI_printf(const char *format, ...);

DLLAPI int        FCGI_vfprintf(FCGI_FILE *fp, const char *format, va_list ap);

DLLAPI int        FCGI_vprintf(const char *format, va_list ap);

DLLAPI size_t     FCGI_fread(void *ptr, size_t size, size_t nmemb, FCGI_FILE *fp);

DLLAPI size_t     FCGI_fwrite(void *ptr, size_t size, size_t nmemb, FCGI_FILE *fp);

DLLAPI int        FCGI_feof(FCGI_FILE *fp);

DLLAPI int        FCGI_ferror(FCGI_FILE *fp);

DLLAPI void       FCGI_clearerr(FCGI_FILE *fp);

DLLAPI FCGI_FILE *FCGI_tmpfile(void);

DLLAPI int        FCGI_fileno(FCGI_FILE *fp);

DLLAPI FCGI_FILE *FCGI_fdopen(int fd, const char *mode);

DLLAPI FCGI_FILE *FCGI_popen(const char *cmd, const char *type);

DLLAPI int        FCGI_pclose(FCGI_FILE *);

/*

 * The remaining definitions are for application programs,

 * not for fcgi_stdio.c

 */

#ifndef NO_FCGI_DEFINES

/*

 * Replace standard types, variables, and functions with FastCGI wrappers.

 * Use undef in case a macro is already defined.

 */

#undef  FILE

#define FILE     FCGI_FILE

#undef  stdin

#define stdin    FCGI_stdin

#undef  stdout

#define stdout   FCGI_stdout

#undef  stderr

#define stderr   FCGI_stderr

#undef  perror

#define perror   FCGI_perror

#undef  fopen

#define fopen    FCGI_fopen

#undef  fclose

#define fclose   FCGI_fclose

#undef  fflush

#define fflush   FCGI_fflush

#undef  freopen

#define freopen  FCGI_freopen

#undef  setvbuf

#define setvbuf  FCGI_setvbuf

#undef  setbuf

#define setbuf   FCGI_setbuf

#undef  fseek

#define fseek    FCGI_fseek

#undef  ftell

#define ftell    FCGI_ftell

#undef  rewind

#define rewind   FCGI_rewind

#undef  fgetpos

#define fgetpos  FCGI_fgetpos

#undef  fsetpos

#define fsetpos  FCGI_fsetpos

#undef  fgetc

#define fgetc    FCGI_fgetc

#undef  getc

#define getc     FCGI_fgetc

#undef  getchar

#define getchar  FCGI_getchar

#undef  ungetc

#define ungetc   FCGI_ungetc

#undef  fgets

#define fgets    FCGI_fgets

#undef  gets

#define gets     FCGI_gets

#undef  fputc

#define fputc    FCGI_fputc

#undef  putc

#define putc     FCGI_fputc

#undef  putchar

#define putchar  FCGI_putchar

#undef  fputs

#define fputs    FCGI_fputs

#undef  puts

#define puts     FCGI_puts

#undef  fprintf

#define fprintf  FCGI_fprintf

#undef  printf

#define printf   FCGI_printf

#undef  vfprintf

#define vfprintf FCGI_vfprintf

#undef  vprintf

#define vprintf  FCGI_vprintf

#undef  fread

#define fread    FCGI_fread

#undef  fwrite

#define fwrite   FCGI_fwrite

#undef  feof

#define feof     FCGI_feof

#undef  ferror

#define ferror   FCGI_ferror

#undef  clearerr

#define clearerr FCGI_clearerr

#undef  tmpfile

#define tmpfile  FCGI_tmpfile

#undef  fileno

#define fileno   FCGI_fileno

#undef  fdopen

#define fdopen   FCGI_fdopen

#undef  popen

#define popen    FCGI_popen

#undef  pclose

#define pclose   FCGI_pclose

#endif /* NO_FCGI_DEFINES */

#if defined (__cplusplus) || defined (c_plusplus)

} /* terminate extern "C" { */

#endif

#endif /* _FCGI_STDIO */