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 sys/types.h 52.In kvm.h 53.Ft struct kinfo_proc * 54.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 55.Ft char ** 56.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 57.Ft char ** 58.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 59.Sh DESCRIPTION 60.Fn kvm_getprocs 61returns a (sub-)set of active processes in the kernel indicated by 62.Fa kd . 63The 64.Fa op 65and 66.Fa arg 67arguments constitute a predicate which limits the set of processes 68returned. The value of 69.Fa op 70describes the filtering predicate as follows: 71.Pp 72.Bl -tag -width 20n -offset indent -compact 73.It Sy KERN_PROC_ALL 74all processes 75.It Sy KERN_PROC_PID 76processes with process id 77.Fa arg 78.It Sy KERN_PROC_PGRP 79processes with process group 80.Fa arg 81.It Sy KERN_PROC_SESSION 82processes with session 83.Fa arg 84.It Sy KERN_PROC_TTY 85processes with tty 86.Fa arg 87.It Sy KERN_PROC_UID 88processes with effective user id 89.Fa arg 90.It Sy KERN_PROC_RUID 91processes with real user id 92.Fa arg 93.El 94.Pp 95If the list of processes should contain all light weight processes, 96add the flag 97.Sy KERN_PROC_FLAG_LWP 98to 99.Fa op . 100.Pp 101The number of processes found is returned in the reference parameter 102.Fa cnt . 103The processes are returned as a contiguous array of kinfo_proc structures. 104This memory is locally allocated, and subsequent calls to 105.Fn kvm_getprocs 106and 107.Fn kvm_close 108will overwrite this storage. 109.Pp 110.Fn kvm_getargv 111returns a null-terminated argument vector that corresponds to the 112command line arguments passed to process indicated by 113.Fa p . 114Most likely, these arguments correspond to the values passed to 115.Xr exec 3 116on process creation. This information is, however, 117deliberately under control of the process itself. 118Note that the original command name can be found, unaltered, 119in the p_comm field of the process structure returned by 120.Fn kvm_getprocs . 121.Pp 122The 123.Fa nchr 124argument indicates the maximum number of characters, including null bytes, 125to use in building the strings. If this amount is exceeded, the string 126causing the overflow is truncated and the partial result is returned. 127This is handy for programs like 128.Xr ps 1 129and 130.Xr w 1 131that print only a one line summary of a command and should not copy 132out large amounts of text only to ignore it. 133If 134.Fa nchr 135is zero, no limit is imposed and all argument strings are returned in 136their entirety. 137.Pp 138The memory allocated to the argv pointers and string storage 139is owned by the kvm library. Subsequent 140.Fn kvm_getprocs 141and 142.Xr kvm_close 3 143calls will clobber this storage. 144.Pp 145The 146.Fn kvm_getenvv 147function is similar to 148.Fn kvm_getargv 149but returns the vector of environment strings. This data is 150also alterable by the process. 151.Sh RETURN VALUES 152.Fn kvm_getprocs , 153.Fn kvm_getargv , 154and 155.Fn kvm_getenvv , 156all return 157.Dv NULL 158on failure. 159.Sh SEE ALSO 160.Xr kvm 3 , 161.Xr kvm_close 3 , 162.Xr kvm_geterr 3 , 163.Xr kvm_nlist 3 , 164.Xr kvm_open 3 , 165.Xr kvm_openfiles 3 , 166.Xr kvm_read 3 , 167.Xr kvm_write 3 168.Sh BUGS 169These routines do not belong in the kvm interface. 170