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. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)kvm_getprocs.3 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD: src/lib/libkvm/kvm_getprocs.3,v 1.6.2.7 2003/04/29 14:37:04 trhodes Exp $ 34.\" $DragonFly: src/lib/libkvm/kvm_getprocs.3,v 1.4 2007/02/01 10:33:25 corecode Exp $ 35.\" 36.Dd June 4, 1993 37.Dt KVM_GETPROCS 3 38.Os 39.Sh NAME 40.Nm kvm_getprocs , 41.Nm kvm_getargv , 42.Nm kvm_getenvv 43.Nd access user process state 44.Sh LIBRARY 45.Lb libkvm 46.Sh SYNOPSIS 47.In sys/types.h 48.In kvm.h 49.Ft struct kinfo_proc * 50.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 51.Ft char ** 52.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 53.Ft char ** 54.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 55.Sh DESCRIPTION 56.Fn kvm_getprocs 57returns a (sub-)set of active processes in the kernel indicated by 58.Fa kd . 59The 60.Fa op 61and 62.Fa arg 63arguments constitute a predicate which limits the set of processes 64returned. The value of 65.Fa op 66describes the filtering predicate as follows: 67.Pp 68.Bl -tag -width 20n -offset indent -compact 69.It Sy KERN_PROC_ALL 70all processes 71.It Sy KERN_PROC_PID 72processes with process id 73.Fa arg 74.It Sy KERN_PROC_PGRP 75processes with process group 76.Fa arg 77.It Sy KERN_PROC_SESSION 78processes with session 79.Fa arg 80.It Sy KERN_PROC_TTY 81processes with tty 82.Fa arg 83.It Sy KERN_PROC_UID 84processes with effective user id 85.Fa arg 86.It Sy KERN_PROC_RUID 87processes with real user id 88.Fa arg 89.El 90.Pp 91If the list of processes should contain all light weight processes, 92add the flag 93.Sy KERN_PROC_FLAG_LWP 94to 95.Fa op . 96.Pp 97The number of processes found is returned in the reference parameter 98.Fa cnt . 99The processes are returned as a contiguous array of kinfo_proc structures. 100This memory is locally allocated, and subsequent calls to 101.Fn kvm_getprocs 102and 103.Fn kvm_close 104will overwrite this storage. 105.Pp 106.Fn kvm_getargv 107returns a null-terminated argument vector that corresponds to the 108command line arguments passed to process indicated by 109.Fa p . 110Most likely, these arguments correspond to the values passed to 111.Xr exec 3 112on process creation. This information is, however, 113deliberately under control of the process itself. 114Note that the original command name can be found, unaltered, 115in the p_comm field of the process structure returned by 116.Fn kvm_getprocs . 117.Pp 118The 119.Fa nchr 120argument indicates the maximum number of characters, including null bytes, 121to use in building the strings. If this amount is exceeded, the string 122causing the overflow is truncated and the partial result is returned. 123This is handy for programs like 124.Xr ps 1 125and 126.Xr w 1 127that print only a one line summary of a command and should not copy 128out large amounts of text only to ignore it. 129If 130.Fa nchr 131is zero, no limit is imposed and all argument strings are returned in 132their entirety. 133.Pp 134The memory allocated to the argv pointers and string storage 135is owned by the kvm library. Subsequent 136.Fn kvm_getprocs 137and 138.Xr kvm_close 3 139calls will clobber this storage. 140.Pp 141The 142.Fn kvm_getenvv 143function is similar to 144.Fn kvm_getargv 145but returns the vector of environment strings. This data is 146also alterable by the process. 147.Sh RETURN VALUES 148.Fn kvm_getprocs , 149.Fn kvm_getargv , 150and 151.Fn kvm_getenvv , 152all return 153.Dv NULL 154on failure. 155.Sh SEE ALSO 156.Xr kvm 3 , 157.Xr kvm_close 3 , 158.Xr kvm_geterr 3 , 159.Xr kvm_nlist 3 , 160.Xr kvm_open 3 , 161.Xr kvm_openfiles 3 , 162.Xr kvm_read 3 , 163.Xr kvm_write 3 164.Sh BUGS 165These routines do not belong in the kvm interface. 166