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DESCRIPTION
The hostid command prints the current host ID number in hexadecimal and both decimal and hexadecimal in parenthesis if the _v option is given. This numeric value is expected to be unique across all hosts and is normally set to resemble the host's Internet address.
Only the superuser can set the hostid by giving an argument. This value is stored in the file /etc/hostid and need only be performed once.
AUTHOR
hostid is written by Mitch D'Souza (m.dsouza@mrc-apu.cam.ac.uk).
SEE ALSO
gethostid(2), sethostid(2)
HOSTNAME
hostname—Show or set the system's hostname
dnsdomainname--Show the system's domain name
SYNOPSIS
hostname [_d][--domain][_Ffilename] [--filefilename] [_f][--fqdn][_h][--help] [--long][_s][--short][_v][--version][name] dnsdomainname
DESCRIPTION
hostname is the program that is used to either set the hostname or display the current host or domain name of the system. This name is used by many of the networking programs to identify the machine.
When called without any arguments, the program displays the current name as set by the hostname command. You can change the output format to display always the short or the long hostname (FQDN). When called with arguments, the program will set the value of the hostname to the value specified. This usually is done only once, at system startup time, by the /etc/rc.d/rc.inet1 configuration script.
Note that only the superuser can change the hostname.
If the program was called as dnsdomainname, it will show the domain name server (DNS) domain name. You can't change the DNS domain name with dnsdomainname. (See the following subsection.)
OPTIONS
| _d, --domain | Display the name of the DNS domain. Don't use the com-mand domainname to get the DNS domain name because it will show the NIS domain name and not the DNS domain name. |
| _F, --file filename | Read the hostname from the specified file. Comments (lines starting with a #) are ignored. |
| _f, --fqdn, --long | Display the FQDN (fully-qualified domain name). An FQDN consists of a short hostname and the DNS domain name. Unless you are using bind or NIS for host lookups, you can change the FQDN and the DNS domain name (which is part of the FQDN) in the /etc/hosts file. |
| _h, --help | Print a usage message on standard output and exit successfully. |
| _s, --short | Display the short hostname. |
| _v, --version | Print version information on standard output and exit successfully. |
FILES
/etc/hosts
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AUTHOR
Peter Tobias, (tobias@server.et-inf.fho-emden.de)
Linux, 28 July 1994
hpcdtoppm v0.3—Convert a Photo-CD file into a portable pixmap
SYNOPSIS
hpcdtoppm [OPTIONS] pcd-file [ppm-file]
DESCRIPTION
hpcdtoppm reads a Photo-CD image file or overview file, and outputs a portable pixmap. Image FILES you can find on the Photo-CD in photo_cd/images are named as imgnnnn.pcd, where nnnn is a 4-digit-number. The Overview file is at photo_cd/overview.pcd. If there is no ppm-file given, output will be printed to stdout. hpcdtoppm stands for "Hadmut's pcdtoppm" to make it distinguishable in case someone else is building the same thing and calling it pcdtoppm.
OPTIONS
| -i | Give some information from the fileheader to stderr. It works only for image FILES. (It is not working correctly, just printing some strings.) |
| -s | Apply simple sharpness-operator on the luma channel. |
| -d | Do not show the complete image, but only the decompressed difference. It works only on the 4Base and the 16Base resolution. It does not have any deeper sense, but it was simple to implement and it shows what causes different sizes of image FILES. |
| -r | Rotate the picture clockwise for portraits. |
| -l | Rotate the picture counter-clockwise for portraits. |
| -a | Try to find out the image orientation. This doesn't work for overview FILES yet. It is very experimental and depends on one byte. Please tell me if it doesn't work. |
| -x | Overskip mode. Works on Base/16, Base/4, Base, and 4Base. In Photo-CD images, the luma channel is stored in full resolution, the two chroma channels are stored in half resolution only and have to be interpolated. In the Overskip mode, the chroma channels of the next higher resolution are taken instead of interpolating. To see the difference, generate one ppm with and one ppm without this flag. Use pnmarith to generate the difference image of these two images. Call ppmhist for this difference or show it with xv (push the HistEq button in the color editor). |
| -1 | -Base/16 | -128x192 | Extract the Base/16 size picture (size 128¥192 pixels). Note that you can only give one size option. |
| -2 | -Base/4 | -256x384 | Extract the Base/4 size picture. |
| -3 | -Base | -512x768 | Extract the Base size picture. |
| -4 | -4Base | -1024x1536 | Extract the 4Base size picture. |
| -5 | -16Base | -2048x3072 | Extract the 16Base size picture. |
| -0 | -Overview | -O |
Extract all pictures from an Overview file. A
ppm filename must be given. If the given name is
foo, the FILES are named foonnnn, where nnnn is a 4-digit number. They are stored in Base/16 format, so they are extracted in this format. |
| -ycc | Suppress the ycc to rgb conversion. This is experimental only. You can use this and apply ppmtorgb3 on the file. Then you will get three pgm FILES, one luma and two chroma FILES. |