.TH PROG 3 .SH NAMEprog \- running programs.SH SYNOPSIS.nf.B bind #p /prog .BI /prog/ n /ctl.BI /prog/ n /dbgctl.BI /prog/ n /exception.BI /prog/ n /fd.BI /prog/ n /heap.BI /prog/ n /ns.BI /prog/ n /nsgrp.BI /prog/ n /pgrp.BI /prog/ n /stack.BI /prog/ n /status.BI /prog/ n /text.BI /prog/ n /wait\&....fi.SH DESCRIPTIONThe.B progdevice serves a two-level directory structure.The first level contains numbered directoriescorresponding to pids of live Limbo processes;each such directory contains a set of filesrepresenting the corresponding process.All files operate on.I UTF(see.IR utf (6))strings..PPThe read-only.B statusfile contains seven space-separated fields.The fields are: the process and process group identifiers, each 8 characters right justified;the user name, at least 10 characters left justified;cpu time in minutes, seconds and tenths of seconds;the process state, 10 characters left justified;the amount of memory used by the process in units of 1024 bytes,at least 5 characters, right justified, followed by a.BR K ;and the name of the current program module,up to 28 characters, left justified..PPThe read-only.B pgrpfile contains the process group identifier, in decimal..PPThe read-only.B nsgrpfile contains the namespace group identifier, in decimal..PPThe read-only.B nsfile contains a set of mount and bind commandswhich describe the.IR sys-bind (2)and.B mountoperations used to construct the name space, inthe format of.IR namespace (6).The lastline of the file is a.B cdcommand indicating the working directory..PPThe read-only.B waitfile may be read to recoverinformation about the exiting children of the process.A read of.B waitwill block until a child of the process, created after.B waitwas opened, exits.When such a child exits, it produces a string with three fields:the pid of the exiting process, a space,module name enclosed in\ \f5"\fP's,a colon,and a possibly empty error message.The error message will contain at most 64 characters..PPThe read-only.B fdfiledescribes the open file descriptors in thefile descriptor group of the process.Each line describes an open file.The fields are: the file descriptor index, the open mode.RB ( r ,.BR w ,.BR rw );the type and number of the device;the path, version and type of the file's.I qid(see.IR intro (5));the file's atomic I/O unit, as defined in.IR sys-iounit (2));the file I/O offset in bytes;and the name with which it was opened..PPThe read-only.B exceptionfile gives details of the last exception to occur in the process, if any. The fieldsare the program counter value when the exception occurred, the module itoccurred in and the exception itself, each separated by a space. If none, theresult is the empty string..PPMessages written to the.B ctlfile control the execution of the process..TF killgrp.PD.TP.B killKill the process..TP.B killgrpKill all processes in the same group as the process.A process writing to its own ctl file does not kill itself..TP.B exceptions propagateApplies to process group leaders only (ie any process that executes a systemcall.I sys->pctl(Sys->NEWPGRP, ...).If any process in the same group as the leader incurs an exception which itdoes not handle, atomically raise the exception in all processes in the group.In this case exceptions are generated for killed processes as well. This mechanism allowsall processes in a process group to perfom error recovery when one of themfaults..TP.B exceptions notifyleaderApplies to process group leaders only.If any process in the same group as the leader incurs an exception which itdoes not handle, atomically destroy all processes in the group except for theleader and raise the exception in the leader. This error recovery mechanism mightbe appropriate when a fault occurs amongst a group of processes and the groupleader takes sole responsibilty for recovery..TP.B restrictedMark all processes that the process spawns in future as restricted. A restrictedprocess is one which can run out of memory when a configured limit has beenreached and before total memory is exhausted. An unrestricted process canallocate memory until memory is truly exhausted. Typically a window manageror server might be unrestricted as they are processes fundamental to therunning of a system..PPThe.B dbgctlfile provides facilities for debugging a process.Messages written to the file control the execution of the process..TP 10n.BI step " n"Step the interpreter for at most.I ninstructions, or until a breakpoint is reached..TP 10n.B toretStep the interpreter until a return from the current activation frameor a breakpoint is reached..TP 10n.B contStep the interpreter until a breakpoint is reached..TP 10n.B stopStop the process as soon as possible.Do not allow the process to execute again until an.B unstopmessage is received..TP 10n.B unstopCancel the effect of any previous.BR stop ..TP 10n.BI "bpt set " "path pc"Set a breakpoint at.I pcfor the module given by.IR path ..TP 10n.BI "bpt del " "path pc"Clear a breakpoint if one exists..PPReading .Bdbgctlgives updates for some state transitions while the process is being debugged.Each update is terminated by a newline..TP 10n.B exitedThe process exited without error..TP 10n.BI broken: " error"The process died due to.IR error ,a string with up to 64 characters..TP 10n.B sendThe process is blocked sending on a channel..TP 10n.B recvThe process is blocked receiving on a channel..TP 10n.B altThe process is blocked in an.B altstatement..TP 10n.B runThe process is unblocked and now ready to run..TP 10n.BI new " pid"The process has spawned a new process identified by.IR pid ..PPThe read-only.B stackfile contains the dynamic call stack trace.Each activation frame is described by one line with six fields, separated by a space:the frame pointer, program counter,module data pointer, and module code pointer,each 8 hexadecimal digits;the execution method for the module (0 means interpreted, 1 compiled);and the path name of the module.The top activation frame starts at offset 0..PPThe.B heapfile may be queried to examine the state of the process.A data query contains an address, a period, a format character,and a count.An instruction query contains a pc, a plus, a mode address, a period,the format.BR I ,and a count.The addresses in the query may be decimal,hexadecimal preceded by.B 0xor.BR 0X ,or octal preceded by.BR 0 .Count gives the number of consecutivedata items retrieved by reading.B heapstarting at offset 0;the format varies according to the format character.All data items other than strings are terminated by a newline..TP 10n.B W32-bit decimal ints..TP 10n.B B8-bit unsigned decimal bytes..TP 10n.B V64-bit decimal bytes..TP 10n.B R64-bit reals..TP 10n.B IDisassembled Dis instructions..TP 10n.B P32-bit hexadecimal address, or.BR nil ..PPThe following formats examine properties of specific 32-bit pointers..TP 10n.B LExamine a list, yieldinga pair of hexadecimal addresses separated by a period,giving the address of the head and tail of a list.It is an error to use.B Lon.BR nil ..TP 10n.B AExamine an array, yieldinga decimal length, a period, and the address of the 0th element of an array,or.BR nil ..TP 10n.B CExamine a string, yieldingthe decimal length in characters, a period, and the.IR utf (6)representation of the string..TP 10n.B MExamine a module reference, yielding the address of its global data or.BR nil ..PPThe.B textfile is currently unimplemented..SH SOURCE.B /emu/port/devprog.c.br.B /os/port/devprog.c