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: src/lib/libkvm/kvm_getprocs.3,v 1.6.2.7 2003/04/29 14:37:04 trhodes Exp $ 38.\" $DragonFly: src/lib/libkvm/kvm_getprocs.3,v 1.2 2003/06/17 04:26:49 dillon Exp $ 39.\" 40.Dd June 4, 1993 41.Dt KVM_GETPROCS 3 42.Os 43.Sh NAME 44.Nm kvm_getprocs , 45.Nm kvm_getargv , 46.Nm kvm_getenvv 47.Nd access user process state 48.Sh LIBRARY 49.Lb libkvm 50.Sh SYNOPSIS 51.In kvm.h 52.In sys/param.h 53.In sys/sysctl.h 54.In sys/user.h 55.\" .Fa kvm_t *kd 56.Ft struct kinfo_proc * 57.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 58.Ft char ** 59.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 60.Ft char ** 61.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 62.Sh DESCRIPTION 63.Fn kvm_getprocs 64returns 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. The value of 72.Fa op 73describes the filtering predicate as follows: 74.Pp 75.Bl -tag -width 20n -offset indent -compact 76.It Sy KERN_PROC_ALL 77all processes 78.It Sy KERN_PROC_PID 79processes with process id 80.Fa arg 81.It Sy KERN_PROC_PGRP 82processes with process group 83.Fa arg 84.It Sy KERN_PROC_SESSION 85processes with session 86.Fa arg 87.It Sy KERN_PROC_TTY 88processes with tty 89.Fa arg 90.It Sy KERN_PROC_UID 91processes with effective user id 92.Fa arg 93.It Sy KERN_PROC_RUID 94processes with real user id 95.Fa arg 96.El 97.Pp 98The number of processes found is returned in the reference parameter 99.Fa cnt . 100The processes are returned as a contiguous array of kinfo_proc structures. 101This memory is locally allocated, and subsequent calls to 102.Fn kvm_getprocs 103and 104.Fn kvm_close 105will overwrite this storage. 106.Pp 107.Fn kvm_getargv 108returns a null-terminated argument vector that corresponds to the 109command line arguments passed to process indicated by 110.Fa p . 111Most likely, these arguments correspond to the values passed to 112.Xr exec 3 113on process creation. This information is, however, 114deliberately under control of the process itself. 115Note that the original command name can be found, unaltered, 116in the p_comm field of the process structure returned by 117.Fn kvm_getprocs . 118.Pp 119The 120.Fa nchr 121argument indicates the maximum number of characters, including null bytes, 122to use in building the strings. If this amount is exceeded, the string 123causing the overflow is truncated and the partial result is returned. 124This is handy for programs like 125.Xr ps 1 126and 127.Xr w 1 128that print only a one line summary of a command and should not copy 129out large amounts of text only to ignore it. 130If 131.Fa nchr 132is zero, no limit is imposed and all argument strings are returned in 133their entirety. 134.Pp 135The memory allocated to the argv pointers and string storage 136is owned by the kvm library. Subsequent 137.Fn kvm_getprocs 138and 139.Xr kvm_close 3 140calls will clobber this storage. 141.Pp 142The 143.Fn kvm_getenvv 144function is similar to 145.Fn kvm_getargv 146but returns the vector of environment strings. This data is 147also alterable by the process. 148.Sh RETURN VALUES 149.Fn kvm_getprocs , 150.Fn kvm_getargv , 151and 152.Fn kvm_getenvv , 153all return 154.Dv NULL 155on failure. 156.Sh BUGS 157These routines do not belong in the kvm interface. 158.Sh SEE ALSO 159.Xr kvm 3 , 160.Xr kvm_close 3 , 161.Xr kvm_geterr 3 , 162.Xr kvm_nlist 3 , 163.Xr kvm_open 3 , 164.Xr kvm_openfiles 3 , 165.Xr kvm_read 3 , 166.Xr kvm_write 3 167