gd_rename man page
gd_rename — change the name of a Dirfile field or alias
int gd_rename(DIRFILE *dirfile, const char *old_code, const char *new_name, unsigned int flags);
The gd_rename() function changes the name of the field or alias specified by old_code, which should not contain a representation suffix, defined in the dirfile specified by dirfile to new_name. If the new name is the same as the old name, this function does nothing and returns no error.
When renaming a metafield, the metafield should be specified in old_code by its full (slashed) field code, while new_name should only contain the new name (without slash).
If old_code specifies a top-level field with meta subfields, the subfields will be renamed, too. By default, this function also updates ALIAS entries whose target contains old_code to point to the new field. Similarly, specifying the GD_REN_UPDB flag will cause this function to modify any field entry containing old_code. As a result, this function may cause more than one metadata fragment to be modified.
The flags parameter should be zero or more of the following flags, bitwise or'd together:
Don't update ALIAS entries, instead turning them into dangling aliases.
if old_code specifies a RAW field, the binary file associated with the field will be renamed as well. Without this flag, no changes are made to the binary file. In this case, the field's I/O pointer will be reset to the beginning-of-frame. If field_code specifies a field of type other than RAW, this flag is ignored.
When updating field metadata (either the target of an alias, or else when specified along with GD_REN_UPDB), skip updating field codes which would be invalid (due to /INCLUDE affixes). Without this flag, such invalid field codes causes this function to fail with the error GD_E_BAD_CODE.
Rename the field in any other field specifications which use this field as an input (either as a vector input field to a derived field, or else as a scalar field parameter). Without this flag, fields which depend on the old name of this field are left unmodified.
On success, gd_rename() returns zero. On error, a negative-valued error code is returned. Possible error codes are:
The specified dirfile was opened read-only.
The library was unable to allocate memory.
The field specified by old_code was not found. Or else the resultant metadata update tried to change a field code into something prohibited by a fragment's affixes.
The supplied dirfile was invalid.
An attempt was made to rename the immutable INDEX field.
The new name specified is already in use by another entry.
An I/O error occurred while attempting to rename the binary file.
The metadata of the format specification fragment containing the renamed entry, or another entry affected by this change, was protected from change, or the binary data of the fragment was protected from change and a binary file move was requested.
The encoding scheme of the specified field could not be determined or was not understood by GetData.
The encoding scheme of the field does not support binary file renaming.
The error code is also stored in the DIRFILE object and may be retrieved after this function returns by calling gd_error(3). A descriptive error string for the error may be obtained by calling gd_error_string(3).
The dirfile_rename() function appeared in GetData-0.5.0. It had no flags argument. In its place was int move_data. Passing a non-zero value for this parameter has the same effect as the GD_REN_DATA flag does now.
In GetData-0.7.0, this function was renamed to gd_rename().
In GetData-0.8.0, the move_data parameter was replaced with the flags parameter. The only flags available were GD_REN_DATA and GD_REN_UBDB.
The flags GD_REN_DANGLE and GD_REN_FORCE flags appeared in GetData-0.9.0.
In GetData-0.10.0, the error return from this function changed from -1 to a negative-valued error code.
gd_error(3), gd_error_string(3), gd_metaflush(3), gd_open(3), dirfile(5), dirfile-format(5)
dirfile-encoding(5), gd_alter_entry(3), gd_getdata(3), gd_move(3).