DtDtsDataToDataType(library call) DtDtsDataToDataType(library call)
NAMEDtDtsDataToDataType — get the data type for a set of data
SYNOPSIS
#include <Dt/Dts.h>
char *DtDtsDataToDataType(
const char *filepath,
const void *buffer,
const int size,
const struct stat *stat_buff,
const char *link_path,
const struct stat *link_stat_buff,
const char *opt_name);
DESCRIPTION
The DtDtsDataToDataType function determines the data type of a set of
data, based on the information given in the non- NULL pointer arguments
to the function. The function gathers any additional information, if
it is needed, to compensate for the NULL arguments. For example, if
the filepath argument is given, but the stat_buff argument is NULL and
a stat_buff value is required to determine the data type, DtDtsDataTo‐
DataType calls the stat(2) function to obtain the information.
The filepath argument is the pathname of a file.
The buffer argument is a pointer to the buffer of the data to be typed.
The size argument is the size of the buffer in bytes.
The stat_buff argument is the buffer returned from a stat(2) or
fstat(3) call for use in typing.
The link_path argument is the pathname of the target file pointed to by
a symbolic link.
The link_stat_buff argument is the buffer returned from an lstat(2)
call for use in typing.
The opt_name argument can be used to specify a name to be associated
with the buffer. If the opt_name argument is not NULL, it is used as a
pseudo file name in typing; otherwise, certain attributes may be
returned as NULL because the filename components could not be deter‐
mined.
RETURN VALUE
Upon successful completion, the DtDtsDataToDataType function returns a
pointer to a data type string, or NULL if no value could be determined.
APPLICATION USAGE
The DtDtsDataToDataType function is generally used by applications such
as file managers to improve performance. Typical applications should
probably use DtDtsFileToDataType(3) or DtDtsBufferToDataType(3)
instead.
The DtDtsBuffer* functions assume that the buffer is readable and
writable by the user, group and other file classes and select a type
accordingly. An application requiring a type based on read-only per‐
missions should use DtDtsDataToDataType with a stat_buff value created
for this purpose: all fields should NULL except for the st_mode field,
which should be set to:
S_IFREG | S_IROTH | S_IRGRP | S_IRUSR
SEE ALSO
Dt/Dts.h, DtDtsLoadDataTypes(3), DtDtsFileToDataType(3), DtDtsBufferTo‐
DataType(3), fstat(3), lstat(2), stat(2).
DtDtsDataToDataType(library call)
