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Diffstat (limited to 'lib/libkvm/kvm_getprocs.3')
| -rw-r--r-- | lib/libkvm/kvm_getprocs.3 | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/lib/libkvm/kvm_getprocs.3 b/lib/libkvm/kvm_getprocs.3 new file mode 100644 index 0000000..15b9b3d --- /dev/null +++ b/lib/libkvm/kvm_getprocs.3 @@ -0,0 +1,164 @@ +.\" Copyright (c) 1992, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" This code is derived from software developed by the Computer Systems +.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract +.\" BG 91-66 and contributed to Berkeley. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)kvm_getprocs.3 8.1 (Berkeley) 6/4/93 +.\" $FreeBSD$ +.\" +.Dd June 4, 1993 +.Dt KVM_GETPROCS 3 +.Os +.Sh NAME +.Nm kvm_getprocs , +.Nm kvm_getargv , +.Nm kvm_getenvv +.Nd access user process state +.Sh LIBRARY +.Lb libkvm +.Sh SYNOPSIS +.In kvm.h +.In sys/param.h +.In sys/sysctl.h +.\" .Fa kvm_t *kd +.Ft struct kinfo_proc * +.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" +.Ft char ** +.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" +.Ft char ** +.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" +.Sh DESCRIPTION +.Fn kvm_getprocs +returns a (sub-)set of active processes in the kernel indicated by +.Fa kd . +The +.Fa op +and +.Fa arg +arguments constitute a predicate which limits the set of processes +returned. The value of +.Fa op +describes the filtering predicate as follows: +.Pp +.Bl -tag -width 20n -offset indent -compact +.It Sy KERN_PROC_ALL +all processes +.It Sy KERN_PROC_PID +processes with process id +.Fa arg +.It Sy KERN_PROC_PGRP +processes with process group +.Fa arg +.It Sy KERN_PROC_SESSION +processes with session +.Fa arg +.It Sy KERN_PROC_TTY +processes with tty +.Fa arg +.It Sy KERN_PROC_UID +processes with effective user id +.Fa arg +.It Sy KERN_PROC_RUID +processes with real user id +.Fa arg +.El +.Pp +The number of processes found is returned in the reference parameter +.Fa cnt . +The processes are returned as a contiguous array of kinfo_proc structures. +This memory is locally allocated, and subsequent calls to +.Fn kvm_getprocs +and +.Fn kvm_close +will overwrite this storage. +.Pp +.Fn kvm_getargv +returns a null-terminated argument vector that corresponds to the +command line arguments passed to process indicated by +.Fa p . +Most likely, these arguments correspond to the values passed to +.Xr exec 3 +on process creation. This information is, however, +deliberately under control of the process itself. +Note that the original command name can be found, unaltered, +in the p_comm field of the process structure returned by +.Fn kvm_getprocs . +.Pp +The +.Fa nchr +argument indicates the maximum number of characters, including null bytes, +to use in building the strings. If this amount is exceeded, the string +causing the overflow is truncated and the partial result is returned. +This is handy for programs like +.Xr ps 1 +and +.Xr w 1 +that print only a one line summary of a command and should not copy +out large amounts of text only to ignore it. +If +.Fa nchr +is zero, no limit is imposed and all argument strings are returned in +their entirety. +.Pp +The memory allocated to the argv pointers and string storage +is owned by the kvm library. Subsequent +.Fn kvm_getprocs +and +.Xr kvm_close 3 +calls will clobber this storage. +.Pp +The +.Fn kvm_getenvv +function is similar to +.Fn kvm_getargv +but returns the vector of environment strings. This data is +also alterable by the process. +.Sh RETURN VALUES +.Fn kvm_getprocs , +.Fn kvm_getargv , +and +.Fn kvm_getenvv , +all return +.Dv NULL +on failure. +.Sh BUGS +These routines do not belong in the kvm interface. +.Sh SEE ALSO +.Xr kvm 3 , +.Xr kvm_close 3 , +.Xr kvm_geterr 3 , +.Xr kvm_nlist 3 , +.Xr kvm_open 3 , +.Xr kvm_openfiles 3 , +.Xr kvm_read 3 , +.Xr kvm_write 3 |
