.TH  "environmental variables" "" "" "Technical Information"
.PC
.PP
The
.I environment
is a set of information that is read by all programs
that run on your system.
It consists of one or more \fIenvironmental variables\fR
that you set.
For example, when you set the environmental variable \fBPATH\fR,
you tell \*(OS that you wish to pass this information to all
programs on your system, including \*(OS itself.
.PP
By changing the environment, you can change the way a command
works without rewriting any commands that you may have
embedded in batch files, scripts, or \fBmakefile\fRs.
.PP
Your programs may request environmental variables of their
own definition.
\*(CO uses the following environmental variables to set its
environment.
Note that the variables marked with an asterisk are used only by the
Korn shell \fBksh\fR.
.LB
\fBASKCC\fR	Have \fBmail\fR prompt for CC names
\fBCWD\fR*	Current working directory
\fBEDITOR\fR	Editor used by default by \fBmail\fR
\fBENV\fR*	File read to set environment
\fBFCEDIT\fR*	Editor used by the \fBfc\fR command
\fBIFS\fR	Characters recognized as white space
\fBHOME\fR	User's home directory
\fBKSH_VERSION\fR*	List current version of Korn shell	
\fBLASTERROR\fR*	Program that last generated an error
\fBLIBPATH\fR	Directories that hold compiler phases and libraries
\fBLOGNAME\fR	Name user's identifier
\fBMAIL\fR	File that holds user's mail messages
\fBMLP_COPIES\fR	Set default number of copies to print
\fBMLP_FORMLEN\fR	Set default page length
\fBMLP_LIFE\fR	Set default life for print jobs
\fBMLP_PRIORITY\fR	Set default priority for print spooling
\fBMLP_SPOOL\fR	Pass user-specific information to print spooler
\fBPAGER\fR	User's preferred output filter
\fBPATH\fR	Directories that hold executable files
\fBPS1\fR	User's default prompt
\fBPS2\fR	Prompt when unbalanced quotation marks span a line
\fBSECONDS\fR*	Number of seconds since current shell started
\fBSHELL\fR	Name the default shell
\fBTERM\fR	Name the default terminal type
\fBTIMEZONE\fR	User's current time zone
\fBTMPDIR\fR	Directory that holds temporary files
\fBUSER\fR	Name user's identifier
.PP
You can also set the following environmental variables to control the default
settings of the \*(CO assembler
\fBas\fR,
the C compiler \fBcc\fR, and
the linker \fBld\fR:
.LB
\fBARHEAD\fR	Append options to beginning of \fBar\fR command line
\fBARTAIL\fR	Append options to end of \fBar\fR command line
\fBASHEAD\fR	Append options to beginning of \fBas\fR command line
\fBASTAIL\fR	Append options to end of \fBas\fR command line
\fBCCHEAD\fR	Append options to beginning of \fBcc\fR command line
\fBCCTAIL\fR	Append options to end of \fBcc\fR command line
\fBCPPHEAD\fR	Append options to beginning of \fBcpp\fR command line
\fBCPPTAIL\fR	Append options to end of \fBcpp\fR command line
\fBLDHEAD\fR	Append options to beginning of \fBld\fR command line
\fBLDTAIL\fR	Append options to end of \fBld\fR command line
.SH "See Also"
.Xr "get_env()," get_env
.Xr "unset," unset
.Xr "Using COHERENT" using_coh
.SH Notes
To delete an environmental variable, use the command
.BR unset .
