Difference between revisions of "Dbupdm()"
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<input parameters> | <input parameters> | ||
| − | char *dbt; | + | char *dbt; /* .DBT file descriptor */ |
| − | char *memo /* Address of a buffer containing the memo to be put into the file | + | char *memo /* Address of a buffer containing the memo to be put into the file */ |
| − | char *oldfield; /* Address of old memo field which should be released, 0 if no reclaim of space is to be made */ | + | char *oldfield; /* Address of old memo field which should be released, 0 if no reclaim of space is to be made */ |
<output parameters> | <output parameters> | ||
| − | char *field; /* Address in the record buffer where the memo is stored | + | char *field; /* Address in the record buffer where the memo is stored */ |
</code> | </code> | ||
| Line 48: | Line 48: | ||
if(rc = dbgetr, (long) 2, record, &status) !=0) { | if(rc = dbgetr, (long) 2, record, &status) !=0) { | ||
| − | printf("Get Memo Failure: % | + | printf("Get Memo Failure: %d\n", rc); |
exit(1); | exit(1); | ||
} | } | ||
if(rc = dbgetm( dbt, &record[53], memobuffer, 0) !=0) { | if(rc = dbgetm( dbt, &record[53], memobuffer, 0) !=0) { | ||
| − | printf("Get Memo Failure: % | + | printf("Get Memo Failure: %d\n", rc); |
exit(1); | exit(1); | ||
} | } | ||
| Line 64: | Line 64: | ||
&record[53], | &record[53], | ||
&record[53]) !=0) { | &record[53]) !=0) { | ||
| − | printf("Memo Update Failure: % | + | printf("Memo Update Failure: %d\n",rc); |
exit(1); | exit(1); | ||
} | } | ||
if(rc = dbupdr(dbf, (long)2, record) !=0) { | if(rc = dbupdr(dbf, (long)2, record) !=0) { | ||
| − | printf("Record Update failure: % | + | printf("Record Update failure: %d\n", rc); |
exit(1); | exit(1); | ||
} | } | ||
Latest revision as of 15:58, 1 May 2009
PURPOSE
update memo in a memo file
SYNOPSIS
#include "dbl.h" int dbpudm(dbt, memo, field, oldfield) <input parameters> char *dbt; /* .DBT file descriptor */ char *memo /* Address of a buffer containing the memo to be put into the file */ char *oldfield; /* Address of old memo field which should be released, 0 if no reclaim of space is to be made */ <output parameters> char *field; /* Address in the record buffer where the memo is stored */
RETURN VALUE
The dbupdm() function returns 0 for success. See the section on return value codes for a detailed list of failure codes.
DESCRIPTION
This function updates a memo in the specified .dbt file. The memo to be updated must first be acquired by using dbgetr() or by other means. The last parameter of this function controls the reallocation of existing memo entries. If the address is specified, the function adds the existing memo entry to the free block list which controls allocation of space in the .dbt file. The address will usually be the same as the third parameter. If no reallocation is desired, the fourth parameter is null (0). This function does not automatically update the memo pointer in the record. The function dbputr() or others that commit records must be used.
EXAMPLE
The following example adds more information to the end of an existing memo entry. Note the use of dbgetr() and dbgetm(). It is assumed that the 4 byte memo pointer starts at the 54th array element (&record[53]).
#include "dbl.h" int dbf, dbt; char record[1000]; char status; int rc; char memobuffer[512]; if(rc = dbgetr, (long) 2, record, &status) !=0) { printf("Get Memo Failure: %d\n", rc); exit(1); } if(rc = dbgetm( dbt, &record[53], memobuffer, 0) !=0) { printf("Get Memo Failure: %d\n", rc); exit(1); } strcat(memobuffer, "This string is appended to the end of the retrieved memo"); if(rc = dbupdm( dbt, memobuffer, &record[53], &record[53]) !=0) { printf("Memo Update Failure: %d\n",rc); exit(1); } if(rc = dbupdr(dbf, (long)2, record) !=0) { printf("Record Update failure: %d\n", rc); exit(1); }
