总览 SYNOPSIS
printcap
描述 DESCRIPTION
Printcap 是 termcap(5) 的簡單版, 用來描述 line printers. 當用到 spool 系統時, 一定會去參考 printcap 這個檔. 允許動態地加入及刪除印表機. 在這資料庫中的每一段敘述代表一台印表機. This data base may not be substituted for, as is possible for termcap, because it may allow accounting to be bypassed.
預設的印表機是 lp, 雖然環境變數 PRINTER 可能優於(override)此. 每一個用到 spool 的軟體都支援 -p 的選項, 用以選擇印表機. 如果想知道如何為一台印表機設定資料的討論, 請參照 4.3 BSD Line Printer Spooler Manual.
相容性 CAPABILITIES
根據 termcap(5) 對檔案輸出的描述.
Name Type Description
af str NULL name of accounting file
br num none if lp is a tty, set the baud
rate (ioctl(2) call)
cf str NULL cifplot data filter
df str NULL tex data filter (DVI format)
fc num 0 if lp is a tty, clear flag
bits (sgtty.h)
ff str ` string to send for a form
feed
fo bool false print a form feed when
device is opened
fs num 0 like `fc' but set bits
gf str NULL graph data filter (plot(3)
format)
hl bool false print the burst header page
last
ic bool false driver supports(non standard)
ioctl to indent printout
if str NULL name of text filter which
does accounting
lf str /dev/console error logging file name
lo str lock name of lock file
lp str /dev/lp device name to open for
output
mx num 1000 maximum file size (in BUFSIZ
blocks), zero = unlimited
nd str NULL next directory for list of
queues (unimplemented)
nf str NULL ditroff data filter (device
independent troff)
of str NULL name of output filtering
program
pc num 200 price per foot or page in
hundredths of cents
pl num 66 page length (in lines)
pw num 132 page width (in characters)
px num 0 page width in pixels
(horizontal)
py num 0 page length in pixels
(vertical)
rf str NULL filter for printing FORTRAN
style text files
rg str NULL restricted group. Only
members of group allowed access
rm str NULL machine name for remote
printer
rp str ``lp'' remote printer name argument
rs bool false restrict remote users to
those with local accounts
rw bool false open the printer device for
reading and writing
sb bool false short banner (one line only)
sc bool false suppress multiple copies
sd str /var/spool/lpd spool directory
sf bool false suppress form feeds
sh bool false suppress printing of burst
page header
st str status status file name
tf str NULL troff data filter (cat
phototypesetter)
tr str NULL trailer string to print when
queue empties
vf str NULL raster image filter
如果本地端印表機(local line printer) driver 支援 indentation 的話, daemon 將知道如何去用它.
过滤器 FILTERS
lpd(8) 守护进程將創造出一個過濾的管線 (pipeline of filters) 來處理各個不同印表機的檔案. 過濾器將依照旗標來選擇將何者送到 lpr(1) . 管線的設定值有:
p pr | if regular text + pr(1)
none If regular text
c cf cifplot
d df DVI (tex)
g gf plot(3)
n nf ditroff
f rf Fortran
t tf troff
v vf raster image
if 過濾器的用法是:
if [-c] -wwidth -llength -iindent -n login -h host acct-file
-c 這個旗標只有在 -l 旗標有列在 lpr 中時才可忽略. width 和 length 定義了 page 的長和寬 (from pw and pl respectively). -n 和 -h 可指定列印工作擁有者的 login name 和 host name. Acct-file 將忽略 printcap 中的描述.
If no if is specified, of is used instead, with the distinction that of is opened only once, while if is opened for every individual job. Thus, if is better suited to performing accounting. The of is only given the width and length flags.
其它過濾器的呼叫用法如下:
filter -xwidth -ylength -n login -h host acct-file
如果要用 pixels 為單位來定長寬的話, 用 px 和 py 這二個變數. 所有的過濾器都經由 stdin 輸入檔案, stdout 輸出到印表機, 用 stderr 或 syslog(3) 來記錄(log), 而且不會忽略 SIGINT.
日志 LOGGING
Error messages generated by the line printer programs themselves (that is, the lp* programs) are logged by syslog(3) using the LPR facility. Messages printed on stderr of one of the filters are sent to the corre- sponding lf file. The filters may, of course, use syslog themselves.
Error messages sent to the console have a carriage return and a line feed appended to them, rather than just a line feed.