HP 3000 Manuals HP 3000 Manuals
Checking the Status of a Procedure Each time a procedure is called, TurboIMAGE/XL returns status information in a buffer specified by the calling program and, if the program is in Compatibility Mode, sets the CM condition code maintained by MPE/iX. The CM condition code, or the TurboIMAGE/XL return status (described later), should be checked immediately after TurboIMAGE/XL returns from the procedure to the calling program before another procedure call is made. A CM condition code is always one of the following and has the general meaning shown: --------------------------------------------------------------------------------------------- | | | | CM Condition Code | General Meaning | | | | --------------------------------------------------------------------------------------------- | | | | CCE | The procedure performed successfully. No | | | exceptional condition was encountered. | | | | --------------------------------------------------------------------------------------------- | | | | CCG | An exceptional condition, other than an error, | | | was encountered. | | | | --------------------------------------------------------------------------------------------- | | | | CCL | The procedure failed due to an invalid parameter | | | or a system error. | | | | --------------------------------------------------------------------------------------------- The first word of the status information returned in the calling program's buffer is a return status whose value corresponds to the CM condition code as follows: --------------------------------------------------------------------------------------------- | | | | CM Condition Code | Return Status Value | | | | --------------------------------------------------------------------------------------------- | | | | CCE | 0 | | | | --------------------------------------------------------------------------------------------- | | | | CCG | >0 | | | | --------------------------------------------------------------------------------------------- | | | | CCL | <0 | | | | --------------------------------------------------------------------------------------------- The calling program must check either the CM condition code or the TurboIMAGE/XL return status to determine the success or failure of the procedure. The return status is also used to indicate various exceptional conditions and errors. See appendix A for a summary. The other elements of status information vary with the outcome of the call and from one procedure to another. The content of these elements is described in detail with each procedure definition later in chapter 5 and in appendix A, which describes error conditions.