HP 3000 Manuals HP 3000 Manuals
HP C/XL Enhancements by Erryl Johnson Systems Technology Division The dollar ($) sign is now a valid character in identifiers. The memcpy ( ) and access ( ) functions in the HP C/XL Library have been enhanced and a new function, memmove ( ), has been added. DOLLAR SIGN IN IDENTIFIERS Dollar ($) signs may be used in an identifier, except as the first character of the identifier. In ANSI mode, dollar signs will be accepted by the compiler only if the +e compiler option is used. In non-ANSI mode, dollar signs will always be accepted. ACCESS ( ) FUNCTION The access ( ) function determines whether a file can be accessed for either read or write. It accomplishes this by opening the specified file and calling FFILEINFO to get the type of access permitted for the file. Prior to XL Release 3.0, the access ( ) function opens the file exclusively. If the file is already open the access function reports that access is not permitted, even though it might be possible to open the file with shared access. In XL Release 3.0 the access ( ) function has been changed to open the file with shared access, which allows access information to be returned for a file that is already open in shared mode. MEMCPY ( ),MEMMOVE ( ) FUNCTIONS The memcpy ( ) function, which copies characters from one memory location to another, has been replaced with a new faster version. The new memcpy (), in order to be fast, does not handle overlapping copies. A new function, memmove ( ), has been added that handles overlapping copies. It may be used wherever memcpy ( ) was required for doing overlapping copies. CHANGE TO TIME ( ) FUNCTION A change that was made to the time ( ) function in XL Release 2.1 has been reversed in XL Release 3.0. This change will allow time ( ) to access the hardware clock, as it did prior to XL Release 2.1. In XL Release 2.1 the time ( ) function was changed to no longer access the hardware clock. Instead time ( ) uses the CALENDAR and CLOCK instrinsics to access the system timer, then adjusts that time according to the user's TZ variable to derive GMT (Greenwich Mean Time). This change was made so that the value returned by time ( ) would not be dependent on the hardware clock being set correctly. This change also made the value returned by time ( ) dependent on the setting of the TZ variable.