Library Functions

The following is a sample program:

/* pxio_sample.c : Sample PxIO console application */ 

/* An error buffer size of 100 will always be large enough. */
#define ERROR_BUFFER_SIZE 100
#define RECORD_SIZE 50

#include <stdio.h> 
#include <string.h> 

#include "PxIO.h" 

int main( int argc, char * argv[])
{
    PxIOFileHandle fileHandle;
    PxIOService serviceHandle;
    const char fileName[] = "testfile";
    inti;
    KeyInfo key;
    RecordInfo record;
    char recordData[20];
    char keyData[5];
    char readBuffer[RECORD_SIZE];
    int status, pxPlusErrorValue;
    char errorBuffer[ERROR_BUFFER_SIZE];
    size_t errorBufferSize = ERROR_BUFFER_SIZE;
    /* This is the default PxPlus field separator. */
    const unsigned char fieldSeparator = 0x8a;

    const char activationString[] = "XXXXXXXXXXXX" ;
    const int activationNumber = 000000000000;

    /* Before we use the PxIO Library we must activate it... */
    status = PxIOActivation(activationString, activationNumber);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* ...and initialize it for single threading by setting the multithread option
    to FALSE. */
    status = PxIOLibInit(FALSE);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* Create a local instance of the library. */
    status = PxIOCreateService(&serviceHandle, NULL, 0, 0, NULL, NULL, NULL);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* Erase any previous test file. */
    status = PxIOErase(serviceHandle, fileName, FALSE);
    if (status < 0)
    {
        /* If the error we encounter is anything other than a missing file error
        (a value of 12), report the error and return. */
        if (PxIOGetError(status, NULL, NULL) != 12)
        {
           pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
            printf( "%s\n" , errorBuffer);
            return status;
        }
    }

    /* Create a keyed file with a record size of RECORD_SIZE, a key size of 4, no
    maximum number of records, a simple key definition, a variable record size, the
    default buffer size, and a field separator that we specify. */
    status = PxIOFileCreate( serviceHandle, fileName, FILE_TYPE_KEYED, RECORD_SIZE,
        4, 0, "[1:1:4]", CREATE_OPTION_VARRECSZ, 0, fieldSeparator);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* Open the file. */
    status = PxIOOpen(serviceHandle, &fileHandle, "testfile" , 0, NULL, 0, 0);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* Add 10 records to the opened file. */
    for (i = 1; i <= 10; ++i)
    {
        /* Create a record. Note the field separator at the end. */
        sprintf( recordData, "Record #%d%c" , i, fieldSeparator);

        record.length = ( int )strlen(recordData);
        record.data = recordData;

        /* Create the key. */
        key.length = 4;
        sprintf(keyData, "%04d" , i);
        key.data = keyData;

        /* Write the data. */
        status = PxIOKeyWrite(fileHandle, &record, &key, TRUE);
        if (status < 0)
        {
            pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
            printf("%s\n" , errorBuffer);
            return status;
        }

        /* Overwrite the field separator, which we put at the end of the record,
        so it looks normal when printing. */
        recordData[strlen(recordData) - 1] = '\0' ;

        printf("Writing record #%d: \"%s\"\n" , i, recordData);
    }

    printf("\n");

    /* Seek to a key in the file. */
    key.length = 4;
    key.data = "0005" ; 
    status = PxIOKeySeek(fileHandle, &key, 0);
    if (status < 0)
    {
         pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* Read the records following the key we specified until the end of the
    file is reached. */
    while (1)
    {
        status = PxIORead(fileHandle, &record, -1, READ_TYPE_NO_OPTIONS);

        /* If we've reached the end of the file, exit the loop. */
        if (PxIOGetError(status, NULL, NULL) == 2) break;

        /* If we've encountered any other error, return from the routine. */
        if (status < 0)
        {
           pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
            printf ( "%s\n" , errorBuffer);
            return status;
        }

        /* Save the record into our buffer. */
        memcpy(readBuffer, record.data, record.length);

        /* Overwrite the field separator, which will be at the end of the record,
        so it looks normal when printing. */
        readBuffer[ record.length - 1] = '\0' ;
        printf("Information read: \"%s\"\n" , readBuffer);
    }

    /* Close the file. */
    status = PxIOClose( fileHandle);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf("%s\n" , errorBuffer);
        return status;
    }

    /* Destroy the local service. */
    status = PxIODestroyService(serviceHandle);
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf( "%s\n" , errorBuffer);
        return status;
    }

    /* We're finished with the PxIO Library, so we shut it down. */
    status = PxIOLibShutDown();
    if (status < 0)
    {
        pxPlusErrorValue = PxIOGetError(status, errorBuffer, &errorBufferSize);
        printf("%s\n" , errorBuffer);
        return status;
    }

     return 0;
}