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<PRE>NAME

cat - concatenate and print files

SYNOPSIS

cat [<B>-u</B>] [<B>-s</B>] [<B>-v</B> [[<B>-t</B>] [<B>-e</B>]] <I>file . . .</I>

DESCRIPTION

cat reads each <I>file</I> in sequence and writes it on  the  standard output.

Thus

cat file

prints the contents of file on your terminal, and

cat file1 file2 &gt;file3

concatenates <B>file1</B> and <B>file2</B>,  and  writes  the  results  in <B>file3</B>.   If 

no input file is given, or if the argument - is encountered, <B>cat</B>  reads  from 

the  standard  input.    <B>cat </B>processes supplementary code set characters

according to the locale specified in the <B>LC_CTYPE</B> environment  variable  [see

LANG on environ(5)].

The following options apply to <B>cat</B>:

<B>-u</B>        The output is not buffered.  (The default  is  buffered output.)

<B>-s</B>        <B>cat</B> is silent about non-existent files.

<B>-v</B>        Causes non-printing characters (with the  exception  of  tabs,

new-lines, and form-feeds) to be      printed visibly. <B>ASCII</B> control characters

 (octal 000 - 037) are  printed as  ^n, where n is the      corresponding <B>ASCII</B>

character in the range octal 100 - 137 (@, A, B, C, . . ., X, Y,  Z,          

 [,       \,  ], ^, and _); the DEL character (octal 0177) is printed <B>^?</B>.  Other

non-printable characters are      printed as <B>M-</B>x, where x is the <B>ASCII</B>

character specified by the low-order seven bits.  All      supplementary code

set characters are considered to be printable.

The following options may be used with the <B>-v</B> option:

<B>-t</B>        Causes tabs to be printed as <B>^I</B>'s and formfeeds  to  be printed

as <B>^L</B>'s.

<B>-e</B>        Causes a <B>$</B> character to be printed at the end  of  each  line

 (prior to the new-line).

The <B>-t</B> and <B>-e</B> options are ignored if the <B>-v</B>  option  is  not specified.

FILES

/usr/lib/locale/<I>locale</I>/LC_MESSAGES/uxcore.abi 

language-specific   message   file   [See <B>LANG</B> on <B>environ</B>(5).]

SEE ALSO

<B>cp</B>(1), <B>pg</B>(1), <B>pr</B>(1)

The <B>NAME</B> section gives the name of the command and a brief description of

what it does.

The <B>SYNOPSIS</B> section shows the command's syntax by listing all possible

options and arguments. Arguments to <B>cat</B> are the names of one or more files. The

fact that <I>file</I> is written in italic type means that <I>file</I> is merely a

placeholder for the name of an actual file. The <B>cat</B> command has three options

and one of them has two &quot;sub-options&quot;. The brackets around options indicate

that they are optional. For example, the command could be any one of the

following:

cat file

cat -u file

cat -s file

cat -u -s file (or cat -s -u file)

cat -us file (or cat -su file)

cat -v file

cat -v -t file (or cat -vt file)

cat -v -e file (or cat -ve file)

cat -v -t -e file (or cat -vte file)

cat -u -v -t file (or cat -uvt file)

and so on. With three options and two suboptions, there are many possible

combinations. Note that the order of writing the options doesn't matter and

options can be combined so that only one dash (-) need be written. While these

are generally true, there are some Unix commands that require a particular

order, some that do not permit combinations and even a few that require a

specific order and deny any combinations.

The <B>DESCRIPTION</B> section is the heart of the manual page. It describes each

option and argument, and frequently contains one or more examples. However, its

explanations are frequently sprinked with referenced to other commands, so that

in general it is difficult to learn about a command from its man page.

The <B>FILES</B> section lists other files that are used or related to the

command.

The <B>SEE ALSO</B> section lists related commands. The numbers in parentheses

refer to the section of the manual in which the command will be found. Among

the most important are:

Section 1 - User Commands

Section 1C - Basic Networking Commands

Section 1M - Administration Commands

Section 2 - System Calls

Section 3 - BSD Routines

Section 3C - C Library Functions

Section 3M - Math Library Functions

Section 3S - Standard I/O Functions

Section 4 - File Formats

Section 5 - Miscellaneous

Section 6 - (not included)

Section 7 - Special Files

Section 8 - System Maintenance Procedures</PRE>

<P>As a user or adminstrator, you will be most interested in section 1 (which contains 1, 1C and 1M). Programmers will be interested in 2, 3 and possibly 4.

<BR></P>

<P>Some man pages have the following additional sections:

<BR></P>

<P>The NOTES section is self-explanatory.

<BR></P>

<P>The DIAGNOSTICS sections contains explanations of error messages that the command may cause to be displayed. Not enough commands have a DIAGNOSTICS section!

<BR></P>

<P>The WARNINGS section describes anything that may limit the use of a command.

<BR></P>

<P>The BUGS section tells of known problems that have not been fixed in the current version of the command.

<BR></P>

<H3 ALIGN="CENTER">

<CENTER><A ID="I15" NAME="I15">

<FONT SIZE=4><B>Finding Information About Disk Utilization with </B><B><I>du</I></B><B> and </B><B><I>df</I></B>

<BR></FONT></A></CENTER></H3>

<P>Occasionally, a user needs to know how much disk space his or her files occupy&#151;perhaps the system administrator has sent e-mail requesting that the user is approaching some sort of limit. Frequently, the system administrator needs the same 
information for all users or on all parts of one or more disks, and frequently needs information on the overall utilization in all file systems. UNIX provides two commands that report that information: du and df.

<BR></P>

<H4 ALIGN="CENTER">

<CENTER><A ID="I16" NAME="I16">

<FONT SIZE=3><B>Summarizing Disk Usage with </B><B><I>du</I></B>

<BR></FONT></A></CENTER></H4>

<P>The du command reports the number of disk blocks used for each directory and subdirectory, and the files found there. It has an option to display the number of blocks of just the &quot;top level&quot; directory.

<BR></P>

<HR ALIGN=CENTER>

<NOTE>

<IMG SRC="note.gif" WIDTH = 35 HEIGHT = 35><B>NOTE:</B> A block is the smallest piece of a disk that can be allocated to a file. Frequently, the size of a block is 512 bytes (but the size depends on things that the system administrator did when setting up 

the disks). A file that is 1 byte long and a file that is 511 bytes long each occupies one block. A 513 byte file and a 1,023 byte file each occupies two blocks. That is, every 512 bytes of a file occupy a disk block, plus one block for the last piece that 

less than 512 bytes.

<BR></NOTE>

<HR ALIGN=CENTER>

<P>Here are some sample executions. First, issue the command to display what you have in the directory hierarchy, from the current directory on down:

<BR></P>

<PRE>$ ls -lR

total 259

drwxr-xr-x   2 pjh      other         48 Oct 17  1990 unixbin

-rw-r&#151;r&#151;   1 pjh      root      130137 May 10  1993 vpix.img

./unixbin:

total 16

-rw-rw-rw-   1 pjh      other       7576 Apr  8  1993 rununix.exe</PRE>

<P>The current directory has one regular file (vpix.img) and one directory file (unixbin), and the subdirectory has one regular file (rununix.exe).

<BR></P>

<P>Now find out the total disk usage:

<BR></P>

<PRE>$ du -s

274     .</PRE>

<P>That's 274 blocks, or somewhere between 13,312 and 13,823 bytes.

<BR></P>

<P>Use the following command to find out how many blocks are in the subdirectory:

<BR></P>

<PRE>$ du

17      ./unixbin

274     .</PRE>

<P>Then find out how many blocks each file has:

<BR></P>

<PRE>$ du -a

16      ./unixbin/rununix.exe

17      ./unixbin

256     ./vpix.img

274     .</PRE>

<HR ALIGN=CENTER>

<NOTE>

<IMG SRC="note.gif" WIDTH = 35 HEIGHT = 35><B>NOTE:</B> The total for a directory or directory hierarchy includes the blocks that the directory files themselves occupy.

<BR></NOTE>

<HR ALIGN=CENTER>

<H4 ALIGN="CENTER">

<CENTER><A ID="I17" NAME="I17">

<FONT SIZE=3><B>Reporting Blocks and Files with </B><B><I>df</I></B>

<BR></FONT></A></CENTER></H4>

<P>The df command helps the system administrator maintain the file systems on the disks. The command displays information about mounted and unmounted resources, types of file systems, and numbers of inodes. It also deals with special devices rather than 
easily identifiable directory paths. Most of these terms have little meaning to the ordinary user, but they are discussed in Chapter 35. However, if a user wants to see what's going on with the disk's file systems, the system permits it.

<BR></P>

<P>Multiple options are available with df. In this section, you'll see some of these options demonstrated and explained. But first, here is a typical result that you get when you invoke df with no options:

<BR></P>

<PRE>$ df

/                  (/dev/root       ):  381964 blocks   58845 files

/proc              (/proc           ):       0 blocks     128 files

/dev/fd            (/dev/fd         ):       0 blocks       0 files

/stand             (/dev/dsk/c0t0d0sa):   12643 blocks     194 files

/var               (/dev/dsk/c0t0d0sb):  961502 blocks   64499 files

/tmp               (/dev/dsk/c0t0d0sd):  191308 blocks   24560 files

/usr               (/dev/dsk/c0t1d0s3):  772900 blocks   53842 files

/home              (/dev/dsk/c0t1d0s4):  923256 blocks   63303 files

/.NetWare          (/.NetWare       ):       0 blocks     499 files</PRE>

<P>The first column is the path name of the file system. This system's special device name appears in the second column. The third column reports the number of disk blocks available on each disk partition. Finally, the last column displays the number of 
files that can be added to each partition. When setting up a new disk, the system administrator partitions it into file systems and allocates several blocks and inodes (or files) to each file system according to how that partition will be used. For 
details, see Chapter 35, &quot;File System Administration.&quot;

<BR></P>

<P>The -b option shows the free space in kilobytes rather than blocks:

<BR></P>

<PRE>$ df -b

Filesystem             avail

/dev/root              190982

/proc                  0

/dev/fd                0

/dev/dsk/c0t0d0sa       6321

/dev/dsk/c0t0d0sb       480751

/dev/dsk/c0t0d0sd       95654

/dev/dsk/c0t1d0s3       386450

/dev/dsk/c0t1d0s4       461628

/.NetWare              0</PRE>

<P>The -k option shows some details about allocated space&#151;how much has been used and how much is available&#151;in kilobytes:

<BR></P>

<PRE>$ df -k

filesystem         kbytes   used     avail    capacity  mounted on

/dev/root          316416   125434   190982   40%       /

/proc              0        0        0         0%       /proc

/dev/fd            0        0        0         0%       /dev/fd

/dev/dsk/c0t0d0sa  10240    3918     6321     38%       /stand

/dev/dsk/c0t0d0sb  509952   29201    480751    6%       /var

/dev/dsk/c0t0d0sd  102368   6714     95654     7%       /tmp

/dev/dsk/c0t1d0s3  512000   125550   386450   25%       /usr

/dev/dsk/c0t1d0s4  512976   51348    461628   10%       /home

/.NetWare          0        0        0         0%       /.NetWare</PRE>

<P>If you are curious about file systems, the -n option tells you the name of the file system type used for each partition. (Again, see Chapter 35 for details.)

<BR></P>

<PRE>$ df -n

/                  : vxfs

/proc              : proc

/dev/fd            : fdfs

/stand             : bfs

/var               : vxfs

/tmp               : vxfs

/usr               : vxfs

/home              : vxfs

/.NetWare          : nucam</PRE>

<P>Finally, the -t option shows used blocks and files, and the total allocation for each file system:

<BR></P>

<PRE>$ df -t

/                  (/dev/root       ):    381964 blocks   58845 files

total:    632832 blocks   65520 files

/proc              (/proc           ):         0 blocks     128 files

total:         0 blocks     202 files

/dev/fd            (/dev/fd         ):         0 blocks       0 files

total:         0 blocks      50 files

/stand             (/dev/dsk/c0t0d0sa):     12643 blocks     194 files

total:     20480 blocks     200 files

/var               (/dev/dsk/c0t0d0sb):    961502 blocks   64499 files

total:   1019904 blocks   65536 files

/tmp               (/dev/dsk/c0t0d0sd):    191308 blocks   24560 files

total:    204736 blocks   24576 files

/usr               (/dev/dsk/c0t1d0s3):    772900 blocks   53842 files

total:   1024000 blocks   65536 files

/home              (/dev/dsk/c0t1d0s4):    923256 blocks   63303 files

total:   1025952 blocks   65536 files

/.NetWare          (/.NetWare       ):         0 blocks     499 files

total:         0 blocks     500 files</PRE>

<H3 ALIGN="CENTER">

<CENTER><A ID="I18" NAME="I18">

<FONT SIZE=4><B>Summary</B>

<BR></FONT></A></CENTER></H3>

<P>UNIX provides several small programs that you can use to quickly obtain information that you frequently need. These programs include the following:

<BR></P>

<UL>

<LI>bc, dc&#151;calculator programs 

<BR>

<BR></LI>

<LI>date and cal&#151;to display time and date

<BR>

<BR></LI>

<LI>finger, who and id&#151;provide user information

<BR>

<BR></LI>

<LI>man and apropos&#151;explains commands

<BR>

<BR></LI>

<LI>su&#151;&quot;switch user&quot;

<BR>

<BR></LI>

<LI>du and df&#151;display information about disk contents

<BR>

<BR></LI></UL>

<P>These commands are rather specialized commands that, in general, retrieve information about different parts of the system: users, files, directories, clock, and so on. The basis of information storage in UNIX is the file, so Chapter 6, &quot;Popular 
File Tools,&quot; explores the somewhat more specialized commands for working with files&#151;particularly text files.</P>

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