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names.c
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1987-11-12
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7KB
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227 lines
/*******************************************************************/
/* NAMES.C */
/* */
/* This example shows how easy it is to write a program for an */
/* online address book using the B-PLUS file indexing toolkit. */
/* The program creates a file of names, addresses, and telephone */
/* numbers. A record is displayed on the screen by entering part */
/* or all of the name. Although the program is usefully as written */
/* it has purposely been kept simple. You may want to add new */
/* features to the progran. */
/* */
/********************************************************************/
#include <stdio.h>
#include <string.h>
#include "bplus.h"
typedef struct /* Here is the address record definition */
{
char lastname[16]; /* last name */
char firstname[16]; /* first name */
char address1[31]; /* first address line */
char address2[31]; /* second address line */
char city[21]; /* the city */
char state[3]; /* the state */
char zipcode[6]; /* postal zip code */
char telephone[14]; /* telephone number */
} ADDRESS;
IX_DESC nameindex; /* index file variable */
FILE *namefile; /* data file pointer */
ADDRESS person; /* data record variable */
void openfiles(void);
void closefiles(void);
int addrecord(void);
void getstring(char*, int);
void newaddress(void);
void printname(ENTRY*);
void getname(void);
void nextname(void);
void listnames(void);
void openfiles()
/* If the file NAMES.DAT already exist, open the index and data */
/* file. Otherwise, these files are created. */
{
if ((namefile = fopen("names.dat","r+")) != NULL)
open_index("names.idx", &nameindex, 1); /* open index file */
else
{
namefile = fopen("names.dat","w+"); /* create data file */
if (namefile == NULL)
{
printf("Unable to open namefile\n");
exit(1);
}
make_index("names.idx", &nameindex, 1); /* creat index file */
} /* allow duplicate keys */
} /* openfiles */
void closefiles()
/* close all files and exit */
{
fclose(namefile);
close_index(&nameindex);
exit(0);
} /* closefiles */
int addrecord()
/* add a new address to the data file - add index to index file */
{
ENTRY ee;
char name[32];
int ret;
ret = fseek(namefile, 0L, SEEK_END); /* seek to end of datafile */
if (ret == 0)
{
strcpy(ee.key, person.lastname); /* key is last name followed */
strcat(ee.key, person.firstname); /* first name. Capitalize */
strupr(ee.key); /* and copy to ee.key. */
ee.recptr = ftell(namefile); /* get position in datafile */
if (ee.recptr != -1L)
{
if (add_key(&ee, &nameindex) == IX_OK) /* add key to index */
{
fwrite(&person,sizeof(person),1,namefile); /* add address */
return (IX_OK);
}
}
}
else printf("Seek error - data file");
return (IX_FAIL);
} /* addrecord */
void getstring(mes, length)
char *mes;
int length;
/* input a string and check that it is not too long */
{
char message[80];
gets(message);
if (strlen(message) > length) message[length] = '\0';
strcpy(mes,message);
} /* getstring */
void newaddress()
/* add new address records */
{
while (1)
{
printf("\n\nLast Name : ");
getstring(person.lastname,15);
if ( strlen(person.lastname) > 0) /* quit if no last name */
{
printf("First Name : ");
getstring(person.firstname,15);
printf("Address Line 1 : ");
getstring(person.address1,30);
printf("Address Line 2 : ");
getstring(person.address2,30);
printf("City : ");
getstring(person.city,20);
printf("State : ");
getstring(person.state,2);
printf("Zip Code : ");
getstring(person.zipcode,5);
printf("Telephone : ");
getstring(person.telephone,13);
addrecord(); /* update data and index files */
printf("\n");
}
else return ;
}
} /* newaddress */
void printname(e)
ENTRY *e;
/* retrieve a data record and print it on the screen */
{
int ret;
/* seek to the record address stored in ENTRY e->recptr */
ret = fseek(namefile, e->recptr, SEEK_SET);
if (ret == 0) /* if OK read the record and display */
{
fread(&person,sizeof(person),1,namefile);
printf("\n\n %s %s" , person.firstname,person.lastname);
printf("\n %s", person.address1);
if (strlen(person.address2) > 0)
printf("\n %s", person.address2);
printf("\n %s, %s %s", person.city,person.state,person.zipcode);
printf("\n %s\n", person.telephone);
}
else printf("Seek error - data file");
} /* printname */
void getname()
/* Get an address record by entering part or all of name */
/* Enter last name first then first name with no spaces */
{
ENTRY ee;
printf("\n\nEnter name: ");
gets(ee.key);
/* make all upper case letters and copy to ee.key */
strupr(ee.key);
/* use locate_key instead of find_key so an exact match not required */
if (locate_key(&ee, &nameindex) != EOIX) printname(&ee);
else printf("No key this large in index file\n");
} /* getname */
void nextname()
/* display the next address in the address file */
{
ENTRY ee;
if (next_key(&ee, &nameindex) == IX_OK) printname(&ee);
else printf("\nEnd of index file\n");
} /* nextname */
void listnames()
/* list all the names in the address file */
{
ENTRY ee;
first_key(&nameindex);
while (next_key(&ee, &nameindex) == IX_OK) printname(&ee);
} /* listnames */
main()
/* Here is the main program loop */
{
char cmd;
int done;
done = 0;
openfiles();
do
{
printf("\nCommand: A (Add Name), F (Find), N (Next), L (List), Q (Quit): ");
cmd = toupper(getche());
switch (cmd)
{
case 'A': newaddress(); break; /* add a name to address file */
case 'F': getname(); break; /* find an address */
case 'N': nextname(); break; /* display next address in file */
case 'L': listnames(); break; /* display all addresses */
case 'Q': closefiles(); /* quit and close files */
}
}
while (!done);
} /* main */