Caché ObjectScript Reference - InterSystems Documentation

$ZF• Spawn a child process to execute a program or command: $ZF(–1) and $ZF(–2).• Load a Dynamic Link Library (DLL) then execute functions from that library: $ZF(–3),$ZF(–4), $ZF(–5), and $ZF(–6).These implementations of $ZF take a negative number as the first parameter. They aredescribed in their own reference pages.Parametersfunction_nameThe name of the function you want to call enclosed in quotation marks, or a negative number.argsThe args parameters are in the form: arg1, arg2, arg3, ...argn. The arguments can consist ofsuch items as descriptions of how arguments are passed and the entry point to the C functionyou are calling.NotesCalling UNIX System Services with $ZFCaché supports error checking functions for use with UNIX system calls from $ZF. Thesecalls allow you to check for asynchronous events and to set an alarm handler in $ZF. Byusing these UNIX functions you can distinguish between real errors, interrupts,and calls that should be restarted.The function declarations are included in cdzf.h and are described in the following table:Declarationint sigrtclr();int dzfalarm();PurposeClears retry flag.Establishes newSIGALRM handler.NotesShould be called once before usingsigrtchk()On entry to $ZF, the previous handler isautomatically saved. On exit, it is restoredautomatically. A user program should notalter the handling of any other signal.Caché ObjectScript Reference 529