Filelist, Lseek – Argox PA-20 Programming Guide User Manual

Page 43

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PT-20 Programming Guide

41

Purpose: Get file length information of a DAT file.

Syntax: long filelength(int fd);

Example call: datasize = filelength(fd);

Includes:

#include “SDK.h ”

Description: The filelength function returns the size in number of bytes of the

DAT file whose file handle is specified in the argument fd.

Returns: The long integer value returned by filelength is the size of the

DAT file in number of bytes. In case of error, filelength returns a

long value of -1 and an error code is set to the global variable

fErrorCode to indicate the error condition encountered. Possible

error codes and their interpretation.

fErrorCode: 2:File specified by fd does not exist.

8:File not opened

filelist

Purpose: Get file directory information.

Syntax: int filelist(char * file_list);

Example call: total_file = filelist(file_list);

Includes:

#include “SDK.h ”

Description: The filelist function copies the file name, file type, and file size

information (separated by a blank character) of all files in

existence into a character array specified in the argument dir.

When char * file_list = NULL,it will pass the length that the file

string needs back.

For example, if there are two files in “C:\Data”, the filename are

StoreIn.dat and StoreOut, and their filesize are 100bytes and 150bytes,

the data in the return buffer is “C:\Data\StoreIn.dat dat 100

C:\Data\

StoreOut.dat dat 150”

Returns:

When “char*file_list” is NULL, it will pass the size of memory

back.

When “char*file_list” is not NULL, it will pass the quantity of file

back.

fErrorCode: None

lseek

Purpose: Move file pointer of a DAT file to a new position.

Syntax: long lseek(int fd, long offset, int origin);

Example call: lseek (fd, 512, 0);

Includes:

#include “SDK.h ”

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