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Examples

Some examples for the usage of the Generic Call Interface follow. All functions are taken from the C-library. The library has the name 'libc' but this may vary for different systems.

C-library's setlocale()

This function has the following syntax:

char * setlocale(int category, const char *locale);

A complete definition is:

InitSetLocale: procedure
setlocale.calltype = 'cdecl'
setlocale.return.type = 'indirect string256' /* more than enough */
setlocale.return.name = 'return value'
setlocale.0 = 2
setlocale.1.type = 'integer32' /* maybe */
setlocale.1.name = 'category'
setlocale.2.type = 'indirect string256' /* more than enough */
setlocale.2.name = 'locale'
err = RxFuncDefine('SETLOCALE', 'libc', 'setlocale', setlocale)
if err \= 0 then
    ...
return
...

DoSetLocale: procedure
/* setlocale.return will be assigned on exit */
setlocale.1.value = arg(1)
setlocale.1.name  = 'category'
setlocale.2.value = arg(2)
setlocale.2.name  = 'locale'
call SETLOCALE setlocale
return setlocale.return.value

or in short:

InitSetLocale: procedure
setlocale.calltype = 'cdecl'
setlocale.return.type = 'indirect string256' /* more than enough */
setlocale.0 = 2
setlocale.1.type = 'integer32' /* maybe */
setlocale.2.type = 'indirect string256' /* more than enough */
err = RxFuncDefine('SETLOCALE', 'libc', 'setlocale', setlocale)
if err \= 0 then
    ...
return
...

DoSetLocale: procedure
/* setlocale.return will be assigned on exit */
setlocale.1.value = arg(1)
setlocale.2.value = arg(2)
call SETLOCALE setlocale
return setlocale.return.value

and even shorter:

InitSetLocale: procedure
setlocale.calltype = 'cdecl as function with parameters'
setlocale.return.type = 'indirect string256' /* more than enough */
setlocale.0 = 2
setlocale.1.type = 'integer32' /* maybe */
setlocale.2.type = 'indirect string256' /* more than enough */
err = RxFuncDefine('SETLOCALE', 'libc', 'setlocale', setlocale)
if err \= 0 then
    ...
return
...

desiredValue = SETLOCALE(arg(1), arg(2))

C-library's getrlimit(), type 1

This function has the following syntax:

int getrlimit(int category, struct rlimit *rlp);

with 

struct rlimit {
    rlim_t rlim_cur;
    rlim_t rlim_max;
}

Note the same types of both entries. It can be interpreted as an array and may have the following definition:

InitGetRLimit1: procedure
getrlimit.calltype = 'cdecl as function'
getrlimit.return.type = 'integer32' /* maybe */
getrlimit.return.name = 'return value'
getrlimit.0 = 2
getrlimit.1.type = 'integer32' /* maybe */
getrlimit.1.name = 'category'
getrlimit.2.type = 'indirect array'
getrlimit.2.name = 'rlp'
getrlimit.2.0 = 2
getrlimit.2.1.type = 'integer32' /* maybe */
getrlimit.2.1.name = 'rlim'
err = RxFuncDefine('GETRLIMIT1', 'libc', 'getrlimit', getrlimit)
if err \= 0 then
    ...
return
...

DoGetRLimit1: procedure
/* the array fields will be assigned on exit */
getrlimit.1.value = arg(1)
getrlimit.2.value = 2
getrlimit.2.1.value = 0
getrlimit.2.2.value = 0
func_rc = GETRLIMIT1(getrlimit)
if func_rc \= 0 then
    ...
return getrlimit.2.1.value ';' getrlimit.2.2.value /* maybe */

C-library's getrlimit(), type 2

This function has the following syntax:

int getrlimit(int category, struct rlimit *rlp);
with 
struct rlimit {
    rlim_t rlim_cur;
    rlim_t rlim_max;
}

The correct form of the definition is:

InitGetRLimit2: procedure
getrlimit.calltype = 'cdecl as function'
getrlimit.return.type = 'integer32' /* maybe */
getrlimit.return.name = 'Return Value'
getrlimit.0 = 2
getrlimit.1.type = 'integer32' /* maybe */
getrlimit.1.name = 'category'
getrlimit.2.type = 'indirect container'
getrlimit.2.name = 'rlp'
getrlimit.2.0 = 2
getrlimit.2.1.type = 'integer32' /* maybe */
getrlimit.2.1.name = 'rlim_cur'
getrlimit.2.2.type = 'integer32' /* maybe */
getrlimit.2.2.name = 'rlim_max'
err = RxFuncDefine('GETRLIMIT2', 'libc', 'getrlimit', getrlimit)
if err \= 0 then
    ...
return
...

DoGetRLimit2: procedure
/* the array fields will be assigned on exit */
getrlimit.1.value = arg(1)
getrlimit.2.value = 2
getrlimit.2.1.value = 0
getrlimit.2.2.value = 0
func_rc = GETRLIMIT2(getrlimit)
if func_rc \= 0 then
    ...
return getrlimit.2.1.value ';' getrlimit.2.2.value /* maybe */

C-library's setrlimit()

This function has the following syntax:

int setrlimit(int category, struct rlimit *rlp);
with rlimit defined as above.

Therefore one can use the above definition to reduce the definition to the lines below if they share the same variable pool which is not the case here. Remove the PROCEDURE instruction of InitGetRLimit2 to get it running. 

InitSetRLimit:
setrlimit.calltype = 'cdecl as function'
setrlimit.return.type = 'integer32' /* maybe */
setrlimit.return.name = 'Return Value'
setrlimit.0 = 2
setrlimit.1.type = 'integer32' /* maybe */
setrlimit.1.name = 'category'
setrlimit.2.type = 'indirect container like getrlimit.2'
setrlimit.2.name = 'rlp'
err = RxFuncDefine('SETRLIMIT', 'libc', 'setrlimit', setrlimit)
if err \= 0 then
    ...
return
...

The use of setrlimit is similar to the example shown above in getrlimit(), type 2

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