Metrologic Optimus R, Руководство по программированию

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Chapter 3 Terminal Specific Function Library 203
Return If successful, it returns 1.
On error, it returns 0.
An error code is set to the global variable fErrorCode to indicate the error
condition encountered. Below are possible error codes and their interpretation.
Error Code Interpretation
2 File specified by
DBF_fd
does not exist.
4 File specified by DBF_fd is not a DBF file.
7 Invalid file handle.
8 File not opened.
10 Not enough free block.
13 Invalid value in argument:
key_number
14 IDX file specified by key_number does not exist.
16 No members exist in the DBF file.
See Also add_member, has_member
get_member
Purpose To read a data record (member) from a DBF file.
Syntax int get_member (int DBF_fd, int key_number, char *buffer);
int DBF_fd; /* file handle of the target DBF file */
int key_number;
/* key no. of the IDX file whose pointer points to the target member */
char *buffer; /* pointer to a buffer where the member is read into */
Example if (get_member (DBF_fd, 1, buffer) == 0) puts (buffer);
Description This routine reads a data record pointed to by the index pointer of an IDX file
(
key_number ), which is associated with a DBF file ( DBF_fd ), into a character
array ( buffer ).
Return If successful, it returns 1.
On error, it returns 0.
An error code is set to the global variable fErrorCode to indicate the error
condition encountered. Below are possible error codes and their interpretation.
Error Code Interpretation
2 File specified by DBF_fd does not exist.
4 File specified by
DBF_fd
is not a DBF file.
7 Invalid file handle.