In this section we will look further at the environment variables passed to the filter. We printed the shell variable values for the filter at the start of the file:
h4: {180} % cat /tmp/lp /tmp/testf -Plp -P lp -Xlp -Ylp /tmp/lp G:' at 01:20:21.560 ENV CONTROL=Hh4.private Ppapowell J/tmp/hi CA Lpapowell Apapowell@h4+105 D2000-04-12-15:27:26.662 Qlp N/tmp/hi fdfA105h4.private UdfA105h4.private HOME=/home/daemon LD_LIBRARY_PATH=/lib:/usr/lib:/usr/5lib:/usr/ucblib LOGDIR=/home/daemon LOGNAME=daemon OPTIND=1 PATH=/bin:/usr/bin:/usr/local/bin PRINTCAP_ENTRY=lp :force_localhost :filter=/tmp/testf :lp=/tmp/lp :sd=/tmp/LPD/lp PRINTER=lp PS1=$ PS2=> SHELL=/bin/sh SPOOL_DIR=/tmp/LPD/lp USER=daemon LEADER hi TRAILER
The HOME, USER, SHELL, PS1, and PS2 variables are usually set by the shell, and are reflect the information for the UID of the user running the shell.
The PATH and LP_LIBRARY_PATH are set by the lpd server to values specified in the printcap or configuration information. It is recommended that users set these to site specific values if the defaults are not suitable for their sites.
The lpd server sets the PRINTER, PRINTCAP_ENTRY, and CONTROL environment variables are set to the printer name, printcap entry, and the control file for the print job. This information is very useful to filters that must make decisions based on values passed to the print server in the control file, and which can also use parameters in the printcap entry to control their actions.
Prev | Home | Next |
Control Files and Filter Options | Up | Using Command Line and Printcap Options In Filters |