1.\" Copyright (c) 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software developed by the Computer Systems 5.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract 6.\" BG 91-66 and contributed to Berkeley. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)kvm_getprocs.3 8.1 (Berkeley) 6/4/93 37.\" $FreeBSD$ 38.\" 39.Dd September 27, 2003 40.Dt KVM_GETPROCS 3 41.Os 42.Sh NAME 43.Nm kvm_getprocs , 44.Nm kvm_getargv , 45.Nm kvm_getenvv 46.Nd access user process state 47.Sh LIBRARY 48.Lb libkvm 49.Sh SYNOPSIS 50.In kvm.h 51.In sys/param.h 52.In sys/sysctl.h 53.In sys/user.h 54.\" .Fa kvm_t *kd 55.Ft struct kinfo_proc * 56.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 57.Ft char ** 58.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 59.Ft char ** 60.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 61.Sh DESCRIPTION 62The 63.Fn kvm_getprocs 64function returns a (sub-)set of active processes in the kernel indicated by 65.Fa kd . 66The 67.Fa op 68and 69.Fa arg 70arguments constitute a predicate which limits the set of processes 71returned. 72The value of 73.Fa op 74describes the filtering predicate as follows: 75.Pp 76.Bl -tag -width 20n -offset indent -compact 77.It Dv KERN_PROC_ALL 78all processes and kernel visible threads 79.It Dv KERN_PROC_PROC 80all processes, without threads 81.It Dv KERN_PROC_PID 82processes with process ID 83.Fa arg 84.It Dv KERN_PROC_PGRP 85processes with process group 86.Fa arg 87.It Dv KERN_PROC_SESSION 88processes with session 89.Fa arg 90.It Dv KERN_PROC_TTY 91processes with TTY 92.Fa arg 93.It Dv KERN_PROC_UID 94processes with effective user ID 95.Fa arg 96.It Dv KERN_PROC_RUID 97processes with real user ID 98.Fa arg 99.It Dv KERN_PROC_INC_THREAD 100modifier to return all kernel visible threads when filtering 101by process ID, process group, TTY, user ID, and real user ID 102.El 103.Pp 104The number of processes found is returned in the reference parameter 105.Fa cnt . 106The processes are returned as a contiguous array of kinfo_proc structures. 107This memory is locally allocated, and subsequent calls to 108.Fn kvm_getprocs 109and 110.Fn kvm_close 111will overwrite this storage. 112.Pp 113The 114.Fn kvm_getargv 115function returns a null-terminated argument vector that corresponds to the 116command line arguments passed to process indicated by 117.Fa p . 118Most likely, these arguments correspond to the values passed to 119.Xr exec 3 120on process creation. 121This information is, however, 122deliberately under control of the process itself. 123Note that the original command name can be found, unaltered, 124in the p_comm field of the process structure returned by 125.Fn kvm_getprocs . 126.Pp 127The 128.Fa nchr 129argument indicates the maximum number of characters, including null bytes, 130to use in building the strings. 131If this amount is exceeded, the string 132causing the overflow is truncated and the partial result is returned. 133This is handy for programs like 134.Xr ps 1 135and 136.Xr w 1 137that print only a one line summary of a command and should not copy 138out large amounts of text only to ignore it. 139If 140.Fa nchr 141is zero, no limit is imposed and all argument strings are returned in 142their entirety. 143.Pp 144The memory allocated to the argv pointers and string storage 145is owned by the kvm library. 146Subsequent 147.Fn kvm_getprocs 148and 149.Xr kvm_close 3 150calls will clobber this storage. 151.Pp 152The 153.Fn kvm_getenvv 154function is similar to 155.Fn kvm_getargv 156but returns the vector of environment strings. 157This data is 158also alterable by the process. 159.Sh RETURN VALUES 160The 161.Fn kvm_getprocs , 162.Fn kvm_getargv , 163and 164.Fn kvm_getenvv 165functions return 166.Dv NULL 167on failure. 168.Sh BUGS 169These routines do not belong in the kvm interface. 170.Sh SEE ALSO 171.Xr kvm 3 , 172.Xr kvm_close 3 , 173.Xr kvm_geterr 3 , 174.Xr kvm_nlist 3 , 175.Xr kvm_open 3 , 176.Xr kvm_openfiles 3 , 177.Xr kvm_read 3 , 178.Xr kvm_write 3 179