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 1.4 2007/02/01 10:33:25 corecode 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 98If the list of processes should contain all light weight processes, 99add the flag 100.Sy KERN_PROC_FLAG_LWP 101to 102.Fa op . 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 113.Fn kvm_getargv 114returns a null-terminated argument vector that corresponds to the 115command line arguments passed to process indicated by 116.Fa p . 117Most likely, these arguments correspond to the values passed to 118.Xr exec 3 119on process creation. This information is, however, 120deliberately under control of the process itself. 121Note that the original command name can be found, unaltered, 122in the p_comm field of the process structure returned by 123.Fn kvm_getprocs . 124.Pp 125The 126.Fa nchr 127argument indicates the maximum number of characters, including null bytes, 128to use in building the strings. If this amount is exceeded, the string 129causing the overflow is truncated and the partial result is returned. 130This is handy for programs like 131.Xr ps 1 132and 133.Xr w 1 134that print only a one line summary of a command and should not copy 135out large amounts of text only to ignore it. 136If 137.Fa nchr 138is zero, no limit is imposed and all argument strings are returned in 139their entirety. 140.Pp 141The memory allocated to the argv pointers and string storage 142is owned by the kvm library. Subsequent 143.Fn kvm_getprocs 144and 145.Xr kvm_close 3 146calls will clobber this storage. 147.Pp 148The 149.Fn kvm_getenvv 150function is similar to 151.Fn kvm_getargv 152but returns the vector of environment strings. This data is 153also alterable by the process. 154.Sh RETURN VALUES 155.Fn kvm_getprocs , 156.Fn kvm_getargv , 157and 158.Fn kvm_getenvv , 159all return 160.Dv NULL 161on failure. 162.Sh SEE ALSO 163.Xr kvm 3 , 164.Xr kvm_close 3 , 165.Xr kvm_geterr 3 , 166.Xr kvm_nlist 3 , 167.Xr kvm_open 3 , 168.Xr kvm_openfiles 3 , 169.Xr kvm_read 3 , 170.Xr kvm_write 3 171.Sh BUGS 172These routines do not belong in the kvm interface. 173