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fstat(8) [bsd man page]

FSTAT(8)						      System Manager's Manual							  FSTAT(8)

fstat - file status SYNOPSIS
fstat [ -u user ] [ -p pid ] [ filename... ] DESCRIPTION
Fstat identifies open files. A file is considered open if a process has it open, if it is the working directory for a process, or if it is an active pure text file. If no options are specified, fstat reports on all open files. Options: -u Report all files open by a specified user. -p Report all files open by a specified process id. filename... Restrict reports to the specified files. If the file is a block special file, fstat additionally reports on any open files on that device, treating it as a mounted file system. The following fields are printed USER The username of the owner of the process. CMD The command name of the process. PID The process id. FD The file number in the per-process open file table. The special names "text" and "wd" mean that the file is the pure text inode or the working directory for the process. If the file number is followed by an asterick (*), then the file is not an inode, but either a socket, fifo, or has an error of some kind. In this case the rest of the entry is variable format, doesn't correspond to the rest of the headings, and is enclosed in parenthesis. The following paragraph describing sockets will explain the variable format. DEVICE Major minor number of the device this file exists on. INODE The inode number of the file. SIZE The size in bytes of the file. TYPE The type of the file. (see sys/file.h) Sockets The formating of open sockets depends on the protocol domain. In all cases the first field is the domain name, the second field is the socket type (stream, dgram, etc), and the third is the socket flags field (in hex). The remaining fields are protocol dependent. For tcp, it is the address of the tcpcb, and for udp, the inpcb (socket pcb). For unix domain sockets, its the address of the socket pcb and the address of the connected pcb (if connected). Otherwise the protocol number and address of the socket itself are printed. The idea is not to duplicate netstat, but to make available enough information for further analysis. For example, the addresses mentioned above are the addresses which the "netstat -A" command would print for tcp, udp, and unixdomain. Note that since pipe(2) is implemented with sock- ets, a pipe appears as a connected unix domain stream socket. A unidirectional unix domain socket indicates the direction of flow with an arrow ("<-" or "->"), and a full duplex socket shows a double arrow ("<->"). BUGS
Socket information clutters the output. Since fstat takes a snapshot of the system, it is only correct for a very short period of time. SEE ALSO
ps(1), pstat(8) 4th Berkeley Distribution December 12, 1987 FSTAT(8)

Check Out this Related Man Page

SOCKSTAT(1)						    BSD General Commands Manual 					       SOCKSTAT(1)

sockstat -- list open sockets SYNOPSIS
sockstat [-clh] [-p ports] [-P pid|process] [-U uid|user] [-G gid|group] DESCRIPTION
The sockstat command lists open Internet or UNIX domain sockets. The following options are available: -c Show connected sockets. -l Show listening sockets. -h Show a usage summary. -p ports Only show Internet sockets if either the local or foreign port number is on the specified list. The ports argument is a comma- separated list of port numbers and ranges specified as first and last port separated by a dash. -P pid|process Only show sockets of the specified pid|process. The pid|process argument is a process name or pid. -U uid|user Only show sockets of the specified uid|user. The uid|user argument is a username or uid. -G gid|group Only show sockets of the specified gid|group. The gid|group argument is a groupname or gid. If neither -c or -l is specified, sockstat will list both listening and connected sockets. The information listed for each socket is: USER The user who owns the socket. COMMAND The command which holds the socket. PID The process ID of the command which holds the socket. FD The file descriptor number of the socket. PROTO The transport protocol associated with the socket for Internet sockets, or the type of socket (stream or datagram) for UNIX sockets. LOCAL ADDRESS For Internet sockets, this is the address the local end of the socket is bound to (see getsockname(2)). For bound UNIX sockets, it is the socket's filename. For other UNIX sockets, it is a right arrow followed by the endpoint's filename, or ``??'' if the endpoint could not be determined. FOREIGN ADDRESS (Internet sockets only) The address the foreign end of the socket is bound to (see getpeername(2)). SEE ALSO
netstat(1), protocols(5) HISTORY
The sockstat command appeared in FreeBSD 3.1. AUTHORS
The sockstat command and this manual page were written by Dag-Erling Smorgrav <>. The sockstat command was ported to Linux by William Pitcock <>. BSD
May 18, 2008 BSD

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