< CALLMON, UTILITIES, Procedure Call Monitor for OpenVMS Alpha 4 CallMon is a low-level debug utility for developers. D With CallMon, an application can monitor all calls to a selected setD of procedures, taken from any shareable image (including the various OpenVMS run-time libraries). D The calls are intercepted whether they are come from the applicationD or from the OpenVMS run-time libraries. For instance, if CallMonD intercepts all calls to LIB$GET_VM, the application will be notifiedD each time LIB$GET_VM is called either from the some module of theD application, from an OpenVMS library routine in some shareable image+ or even from another routine in LIBRTL.EXE. D CallMon is especially useful to implement higher level tools whichD need to monitor the activity of some library routines. A typicalD usage of CallMon may be the monitoring of the virtual memoryD allocation (intercepting calls to routines like LIB$GET_VM and
LIB$FREE_VM). 5 To intercept a routine, the application must provide: ? - the name of the routine to intercept (a character string) : - the address of a user-written pre-processing routine; - the address of a user-written post-processing routine D Later, whenever the intercepted routine is called, the following steps are taken: 8 - the user-written pre-processing routine is called,1 - the original intercepted routine is called, 9 - the user-written post-processing routine is called. D The user-written procedures have access to the original argumentD list and returned value. The interception can be activated, modifiedD and deactivated at any time. All hooks into the code are performed9 "on the fly" in the virtual address space of the process. D Interface definition files are provided for the C and Ada languages.5 However, CallMon can be used from any other language. D Note that CallMon is designed for OpenVMS Alpha only. CallMon uses aD lot of features which are specific to the Alpha architecture and toD the structure of OpenVMS on Alpha platforms. There is currently no% version of CallMon for VAX platforms. D This OpenVMS Freeware CD contains the version 1.0 of CallMon. You9 will find the following items in the [CALLMON] directory: ; - CALLMON.PS : CallMon documentation in PostScript form * - CALLMON.OLB : CallMon object library8 - CALLMON.H and CALLMONMSG.H : Interface files for C@ - CALLMON_.ADA and CALLMONMSG_.ADA : Interface files for AdaB - [.SRC]*.* : CallMon source files (written in C and Macro-64)B - CALLMON$RESIDENT.COM : Utility procedure (see documentation) D Several example programs written in C and Ada are provided. TheirD source files are located in the subdirectory [.SRC]. The correspon-: ding executable images are provided in the main directory. $ RELEASE FORM$ ------------ OpenVMS Freeware CD -------------------- DEVELOPER RELEASE FORM: C As the owner/developer of this software, I release it to be J included on the OpenVMS Freeware CD-ROM. I expect no renumerancesJ or payments for the use of this software from Digital or Digital's customers. ? _______________________ 8 Thierry Lelegard
