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Changes the base priority of the process. The base priority is used to determine the order in which executable processes are to run.
SYS$SETPRI [pidadr] ,[prcnam] ,pri ,[prvpri] ,[nullarg] ,[nullarg]
int sys$setpri (unsigned int *pidadr, void *prcnam, unsigned int pri, unsigned int *prvpri, unsigned int *pol, unsigned int *prvpol);
pidadr
OpenVMS usage: process_id type: longword (unsigned) access: modify mechanism: by reference
Process identification (PID) of the process whose priority is to be set. The pidadr argument is the address of the PID. The pidadr argument can refer to a process running on the local node or a process running on another node in the cluster.prcnam
OpenVMS usage: process_name type: character-coded text string access: read only mechanism: by descriptor--fixed-length string descriptor
Process name of the process whose priority is to be changed. The prcnam argument is the address of a character string descriptor pointing to the process name.A process running on the local node can be identified with a 1- to 15-character string. To identify a process on a particular node on a cluster, specify the full process name, which includes the node name as well as the process name. The full process name can contain up to 23 characters.
You can use the prcnam argument only on behalf of processes in the same UIC group as the calling process. To set the priority for processes in other groups, you must specify the pidadr argument.
pri
OpenVMS usage: longword_unsigned type: longword (unsigned) access: read only mechanism: by value
New base priority to be established for the process. The pri argument is a longword value containing the new priority. Priorities that are not real time are in the range 0 through 15; real-time priorities are in the range 16 through 31.If the specified priority is higher than the base priority of the target process, and if the caller does not have ALTPRI privilege, then the base priority of the target process is used.
prvpri
OpenVMS usage: longword_unsigned type: longword (unsigned) access: write only mechanism: by reference
Base priority of the process before the call to $SETPRI. The prvpri argument is the address of a longword into which $SETPRI writes the previous base priority of the process.policy
OpenVMS usage: longword_unsigned type: longword (unsigned) access: read only mechanism: by reference
On Alpha and Integrity server systems, address of a longword containing the new scheduling policy for the process.The $JPIDEF macro defines the following symbols for the policy argument:
Symbol Meaning JPI$K_DEFAULT_POLICY The normal scheduling policy. The priority interval for this policy is defined as [0.. n], such that priorities [0..15] are interactive and priorities [16.. n] are real time. JPI$K_PSX_FIFO_POLICY POSIX FIFO scheduling policy. The priority interval for this policy is defined as [ n.. m] real-time priorities. JPI$K_PSX_RR_POLICY POSIX round-robin policy. The priority interval for this policy is defined as [ n.. m] real-time priorities. prvpol
OpenVMS usage: longword_unsigned type: longword (unsigned) access: write only mechanism: by reference
On Alpha and Integrity server systems, address of a longword into which the previous scheduling policy for the process is written. If the policy argument is null, no change in policy is requested and prvpol returns the current policy.The valid priority intervals for specific scheduling policies might change in the future. Applications should, therefore, not use embedded numeric constants for scheduling priority, but should use the appropriate $GETSYI item codes to fetch the legal priority intervals. The application can then dynamically select a priority value that is within the interval. The $GETSYI item codes are:
- SYI$_DEF_PRIO_MAX, SYI$_DEF_PRIO_MIN
- SYI$_PSXFIFO_PRIO_MAX, SYI$_PSXFIFO_PRIO_MIN
- SYI$_PSXRR_PRIO_MAX, SYI$_PSXRR_PRIO_MIN
See the Item Codes section of the $GETSYI service description for more information about these item codes.
nullarg
OpenVMS usage: null_arg type: longword (unsigned) access: read only mechanism: by value
Placeholding argument reserved to HP.
The Set Priority service changes the base priority of the process or, optionally, changes the scheduling policy of the process. The base priority is used to determine the order in which executable processes are to run.The scheduling policy denotes the following:
- The basic scheduling discipline (FIFO, round-robin, and so forth).
- The preemption/compensation rules by which a running process is descheduled in favor of another process and, ultimately, rescheduled.
A source process can modify the priority or scheduling policy of a target process if any of the following are true:
- The source and target processes are in the same job tree.
- The source and target processes have the same UIC.
- The source process has WORLD privilege enabled.
- The source and target processes are in the same process group.
The value to which the priority of a process can be set can be subject to limitations. If the source has ALTPRI privilege enabled, the target can be set to any valid priority. Otherwise, the priority value specified by the source process is compared to the authorized priority of the target process and the smaller of the two values is used as the new base priority of the target process.
If you specify neither the pidadr nor the prcnam argument, $SETPRI sets the base priority of the calling process.
If the longword at address pidadr is the value 0, the PID of the target process is returned.
The base priority of a process remains in effect until specifically changed or until the process is deleted.
To determine the priority set by the $SETPRI service, use the Get Job/Process Information ($GETJPI) service.
Depending on the operation, the calling process might need one of the following privileges to use $SETPRI:
- GROUP privilege to change the priority of a process in the same group, unless the target process has the same UIC as the calling process.
- WORLD privilege to change the priority of any other process in the system.
- ALTPRI privilege to set any process's priority to a value greater than the target process's initial base priority. If a process does not have ALTPRI privilege, the priority value specified by the source process is compared to the authorized priority of the target process and the smaller of the two values is used as the new base priority of the target process.
None
$CANEXH, $CREPRC, $DCLEXH, $DELPRC, $EXIT, $FORCEX, $GETJPI, $GETJPIW, $HIBER, $PROCESS_SCAN, $RESUME, $SETPRN, $SETPRV, $SETRWM, $SUSPND, $WAKE
SS$_NORMAL The service completed successfully. SS$_ACCVIO The process name string or string descriptor cannot be read by the caller, or the process identification or previous priority longword cannot be written by the caller. SS$_ILLPOLICY An invalid scheduling policy was specified. SS$_ILLPRIPOL Setting the process to the specified priority and/or policy would result in an illegal policy/priority combination. The illegal combination can occur between the SETPRI policy and priority parameters themselves, or it can occur between either of the parameters and the current policy and/or priority of the target process. SS$_INCOMPAT The remote node is running an incompatible version of the operating system. SS$_IVLOGNAM The process name string has a length of 0 or has more than 15 characters. SS$_NONEXPR The specified process does not exist, or an invalid process identification was specified. SS$_NOPRIV The process does not have the privilege to affect other processes. SS$_NOSUCHNODE The process name refers to a node that is not currently recognized as part of the cluster. SS$_REMRSRC The remote node has insufficient resources to respond to the request. (Bring this error to the attention of your system manager.) SS$_UNREACHABLE The remote node is a member of the cluster but is not accepting requests. (This is normal for a brief period early in the system boot process.)
Allows a process to establish or to change its own process name.
SYS$SETPRN [prcnam]
int sys$setprn (void *prcnam);
prcnam
OpenVMS usage: process_name type: character-coded text string access: read only mechanism: by descriptor--fixed-length string descriptor
Process name to be given to the calling process. The prcnam argument is the address of a character string descriptor pointing to a 1- to 15-character process name string. If you do not specify prcnam, the calling process is given no name.
The Set Process Name service allows a process to establish or to change its own process name, which remains in effect until you change it (using $SETPRN) or until the process is deleted. Process names provide an identification mechanism for processes executing with the same group number. A process can also be identified by its process identification (PID).None
None
$CANEXH, $CREPRC, $DCLEXH, $DELPRC, $EXIT, $FORCEX, $GETJPI, $GETJPIW, $HIBER, $PROCESS_SCAN, $RESUME, $SETPRI, $SETPRV, $SETRWM, $SUSPND, $WAKE
SS$_NORMAL The service completed successfully. SS$_ACCVIO The process name string or string descriptor cannot be read by the caller. SS$_DUPLNAM The specified process name duplicates one already specified within that group. SS$_IVLOGNAM The specified process name has a length of 0 or has more than 15 characters.
Allows a process to change the protection on a page or range of pages.
SYS$SETPRT inadr ,[retadr] ,[acmode] ,prot ,[prvprt]
int sys$setprt (struct _va_range *inadr, struct _va_range *retadr, unsigned int acmode, unsigned int prot, unsigned char *prvprt);
inadr
OpenVMS usage: address_range type: longword (unsigned) access: read only mechanism: by reference
Starting and ending virtual addresses of the range of pages whose protection is to be changed. The inadr argument is the address of a 2-longword array containing, in order, the starting and ending process virtual addresses.Addresses are adjusted up or down to fall on CPU-specific page boundaries. Only the virtual page number portion of each virtual address is used; the low-order byte-within-page bits are ignored.
If the starting and ending virtual addresses are the same, the protection is changed for a single page.
retadr
OpenVMS usage: address_range type: longword (unsigned) access: write only mechanism: by reference---array reference or descriptor
Starting and ending virtual addresses of the range of pages whose protection was actually changed by $SETPRT. The retadr argument is the address of a 2-longword array containing, in order, the starting and ending process virtual addresses.If an error occurs while the protection is being changed, $SETPRT writes into retadr the range of pages that were successfully changed before the error occurred. If no pages were affected before the error occurred, $SETPRT writes the value --1 into each longword of the 2-longword array.
acmode
OpenVMS usage: access_mode type: longword (unsigned) access: read only mechanism: by value
Access mode associated with the call to $SETPRT. The acmode argument is a longword containing the access mode. The $PSLDEF macro defines symbols for the access modes.The $SETPRT service uses whichever of the following two access modes is least privileged: (1) the access mode specified by acmode or (2) the access mode of the caller. To change the protection of any page in the specified range, the resultant access mode must be equal to or more privileged than the access mode of the owner of that page.
prot
OpenVMS usage: page_protection type: longword (unsigned) access: read only mechanism: by value
Page protection to be assigned to the specified pages. The prot argument is a longword value containing the protection code. Only bits 0 to 3 are used; bits 4 to 31 are ignored.The $PRTDEF macro defines the following symbolic names for the protection codes:
Symbol Description PRT$C_NA No access PRT$C_KR Kernel read only PRT$C_KW Kernel write PRT$C_ER Executive read only PRT$C_EW Executive write PRT$C_SR Supervisor read only PRT$C_SW Supervisor write PRT$C_UR User read only PRT$C_UW User write PRT$C_ERKW Executive read; kernel write PRT$C_SRKW Supervisor read; kernel write PRT$C_SREW Supervisor read; executive write PRT$C_URKW User read; kernel write PRT$C_UREW User read; executive write PRT$C_URSW User read; supervisor write OpenVMS Alpha and Integrity server systems convert PRT$C_NA to the next highest protection, kernel-read.
If you specify the protection as the value 0, the protection defaults to kernel read only.
prvprt
OpenVMS usage: page_protection type: byte (unsigned) access: write only mechanism: by reference
Protection previously assigned to the last page in the range. The prvprt argument is the address of a byte into which $SETPRT writes the protection of this page. The prvprt argument is useful only when protection for a single page is being changed.
The Set Protection on Pages service allows a process to change the protection on a page or range of pages.None
If a process changes the protection for any pages in a private section from read only to read/write, $SETPRT uses the paging file (PGFLQUOTA) quota of the process.
For pages in global sections, the new protection can alter only copy-on-reference pages.
$ADJSTK, $ADJWSL, $CRETVA, $CRMPSC, $DELTVA, $DGBLSC, $EXPREG, $LCKPAG, $LKWSET, $MGBLSC, $PURGWS, $SETSTK, $SETSWM, $ULKPAG, $ULWSET, $UPDSEC, $UPDSECW
SS$_NORMAL The service completed successfully. SS$_ACCVIO The input address array cannot be read by the caller; the output address array or the byte to receive the previous protection cannot be written by the caller; or an attempt was made to change the protection of a nonexistent page. SS$_EXQUOTA The process exceeded its paging file quota while changing a page in a read-only private section to a read/write page. SS$_IVPROTECT The specified protection code has a numeric value of 1, less than 0, or greater than 15. SS$_LENVIO A page in the specified range is beyond the end of the program or control region. SS$_NOPRIV A page in the specified range is in the system address space; an attempt was made to change the protection of a valid global page, of an invalid global noncopy-on-reference page, or a PFN global or private page. SS$_PAGOWNVIO The process attempted to change the protection on a page owned by a more privileged access mode.
On Alpha and Integrity server systems, allows a process to change the protection on a page or range of pages.This service accepts 64-bit addresses.
SYS$SETPRT_64 start_va_64 ,length_64 ,acmode ,prot ,return_va_64 ,return_length_64 ,return_prot_64
int sys$setprt_64 (void *start_va_64, unsigned __int64 length_64, unsigned int acmode, unsigned int prot, void *(*(return_va_64)), unsigned __int64 *return_length_64, unsigned int *return_prot_64);
start_va_64
OpenVMS usage: address type: quadword address access: read only mechanism: by value
The starting virtual address of the range of pages whose protection is to be changed. The specified virtual address will be rounded down to a CPU-specific boundary.length_64
OpenVMS usage: byte count type: quadword (unsigned) access: read only mechanism: by value
Length of the virtual address space whose protection is to be changed. The specified length will be rounded up to a CPU-specific page boundary so that it includes all CPU-specific pages in the requested range.acmode
OpenVMS usage: access_mode type: longword (unsigned) access: read only mechanism: by value
Access mode associated with the call to $SETPRT_64. The acmode argument is a longword containing the access mode.The $PSLDEF macro in STARLET.MLB and the file PSLDEF.H in SYS$STARLET_C.TLB define the following symbols and their values for the four access modes:
Value Symbolic Name Access Mode 0 PSL$C_KERNEL Kernel 1 PSL$C_EXEC Executive 2 PSL$C_SUPER Supervisor 3 PSL$C_USER User The most privileged access mode used is the access mode of the caller. To change the protection of any page in the specified range, the resultant access mode must be equal to or more privileged than the access mode of the owner of that page.
prot
OpenVMS usage: page_protection type: longword (unsigned) access: read only mechanism: by value
Page protection to be assigned to the specified pages. The prot argument is a longword value containing the protection code. Only bits 0 to 3 are used; bits 4 to 31 are ignored.The $PRTDEF macro for MACRO-32 and the include file PRTDEF.H for C define the symbolic names for the protection codes.
return_va_64
OpenVMS usage: address type: quadword address access: write only mechanism: by 32- or 64-bit reference
The lowest process virtual address of the range of pages whose protection was actually changed. The return_va_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the virtual address.return_length_64
OpenVMS usage: byte count type: quadword (unsigned) access: write only mechanism: by 32- or 64-bit reference
The length of the virtual address range whose protection was actually changed. The return_length_64 argument is the 32- or 64-bit virtual address of a naturally aligned quadword into which the service returns the length of the virtual address range in bytes.return_prot_64
OpenVMS usage: page_protection type: longword (unsigned) access: write only mechanism: by 32- or 64-bit reference
Protection previously assigned to the last page in the range. The return_prot_64 argument is the 32- or 64-bit virtual address of a naturally aligned longword into which $SETPRT_64 writes the protection of this page. The return_prot_64 argument is useful only when protection for a single page is being changed.
The Set Protection on Pages service allows a process to change the protection on a page or range of pages. For pages in a global section, the new protection can alter only copy-on-reference pages.
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