gd_get_string(3) [debian man page]

gd_get_string(3)						      GETDATA							  gd_get_string(3)

NAME

       gd_get_string -- retrieve a string from a dirfile database

SYNOPSIS

       #include <getdata.h>

       size_t gd_get_string(DIRFILE *dirfile, const char *field_code, size_t len, char *data_out);

DESCRIPTION

       The  gd_get_string() function queries a dirfile(5) database specified by dirfile for the string scalar field_code, which should not contain
       a representation suffix.  The first len characters of the string scalar are stored in the user-supplied buffer data_out.

       The dirfile argument must point to a valid DIRFILE object previously created by a call to gd_open(3).

       If len equals zero, or if data_out equals NULL, no data will be copied to data_out, but the length of the string scalar will still  be  re-
       turned  by gd_get_string().  Otherwise, the argument data_out must point to a valid memory location of sufficient size to hold at least len
       characters.  If the length of the string scalar is greater than len, data_out will not be NULL-terminated.

RETURN VALUE

       On success, gd_get_string() returns the actual length of the specified string scalar, including the trailing NULL character.  A return val-
       ue greater than len indicates that the output string is not null terminated.

       On error, it returns 0 and sets the dirfile error to a non-zero value.  Possible error values are:

       GD_E_BAD_CODE
	       The field specified by field_code was not found in the database.

       GD_E_BAD_DIRFILE
	       An invalid dirfile was supplied.

       GD_E_BAD_FIELD_TYPE
	       The  supplied field_code referred to a field of type other than STRING.	The caller should use gd_getdata(3), or gd_get_constant(3)
	       instead.

       GD_E_BAD_TYPE
	       An invalid return_type was specified.

       GD_E_INTERNAL_ERROR
	       An internal error occurred in the library while trying to perform the task.  This indicates a bug in the  library.   Please  report
	       the incident to the maintainer.

       The  dirfile error may be retrieved by calling gd_error(3).  A descriptive error string for the last error encountered may be obtained from
       a call to gd_error_string(3).

SEE ALSO

       dirfile(5), gd_open(3), gd_error(3), gd_error_string(3), gd_put_string(3)

Version 0.7.0							    25 May 2010 						  gd_get_string(3)

gd_bof(3)							      GETDATA								 gd_bof(3)

NAME

       gd_bof -- report the start of data in a field

SYNOPSIS

       #include <getdata.h>

       off_t gd_bof(DIRFILE *dirfile, const char *field_code);

DESCRIPTION

       The gd_bof() function queries a dirfile(5) database specified by dirfile and returns the sample number of the beginning-of-field marker for
       the vector field given by field_code.

       The caller should not assume that the beginning-of-field marker falls on a frame boundary.  The beginning-of-field marker  is  never  nega-
       tive.

       For  a RAW field, the beginning-of-field corresponds to the frame offset of that field (see gd_frameoffset(3)).	The beginning-of-field for
       all other vector field type is the same as the beginning-of-field of whichever of its input fields that starts latest.	The  beginning-of-
       field marker for the special field INDEX is always zero.

       The beginning-of-field marker for a field containing no data is in the same location as, or after, its end-of-field marker (see gd_eof(3)).
       For a RAW field, the difference between the locations of the beginning- and end-of-field markers indicates the number of  samples  of  data
       actually stored on disk.

       The dirfile argument must point to a valid DIRFILE object previously created by a call to gd_open(3).

RETURN VALUE

       Upon successful completion, gd_bof() returns the sample number of the end-of-field marker for the indicated field.  On error, it returns -1
       and sets the dirfile error to a non-zero error value.  Possible error values are:

       GD_E_BAD_CODE
	       The field specified by field_code or one of the fields it uses as input was not found in the database.

       GD_E_BAD_DIRFILE
	       The supplied dirfile was invalid.

       GD_E_BAD_REPR
	       The representation suffix specified in field_code, or in one of its inputs was not recognised.

       GD_E_DIMENSION
	       A scalar field was found where a vector field was expected in the definition of field_code or one of its inputs, or else field_code
	       itself specified a scalar field.

       GD_E_RECURSE_LEVEL
	       Too  many levels of recursion were encountered while trying to resolve field_code.  This usually indicates a circular dependency in
	       field specification in the dirfile.

       The dirfile error may be retrieved by calling gd_error(3).  A descriptive error string for the last error encountered can be obtained  from
       a call to gd_error_string(3).

SEE ALSO

       dirfile(5), dirfile-encoding(5), gd_open(3), gd_eof(3), gd_error(3), gd_error_string(3), gd_nframes(3)

Version 0.7.0							  15 October 2010							 gd_bof(3)