ISA - Determines whether a variable is of a certain type, class, or structure name.
GET_LOGIN_INFO - Returns the name of the computer running the IDL process, as well as the user’s login name.
QUERY_ASCII - Obtains information about an ASCII file.
QUERY_BMP - Obtains information about a BMP image file.
QUERY_CSV - Obtains information about a comma-separated values (CSV) file.
QUERY_DICOM - Tests file for compatibility with READ_DICOM.
QUERY_GIF - Obtains information about a GIF image file.
QUERY_IMAGE - Determines if a file is recognized as an image file.
QUERY_JPEG - Obtains information about a JPEG image file.
QUERY_JPEG2000 - Obtains information about a JPEG 2000 image file.
QUERY_MRSID - Obtains information about a MrSID image file.
QUERY_PICT - Obtains information about a PICT image file.
QUERY_PNG - Obtains information about a PNG image file.
QUERY_PPM - Obtains information about a PPM image file.
QUERY_SRF - Obtains information about an SRF image file.
QUERY_TIFF - Obtains information about a TIFF image file.
QUERY_WAV - Checks that the file is actually a .WAV file and that the READ_WAV function can read the data in the file.
ROUTINE_FILEPATH - Returns the full path to a currently-compiled procedure or function (or a list of procedures and functions).
TYPENAME - Retrieves a variable’s IDL type name, class name, or structure name.