AT&T UNIX™PC Unix System V Users Manual - tenox

KSH ( 1)
KSH ( 1)
${parameter%pattern }
${parameter%%pattern }
If the Korn Shell pattern matches the end of the value of
parameter, then substitute the value of parameter with
the matched part deleted; otherwise substitute the value
of parameter.
In the above, word is not evaluated unless it is to be used as the
substituted string, so that, in the following example, pwd is executed
only if d is not set or is null:
echo ${d:- 'pwd'}
If the colon ( :) is omitted from the above expressions, then the
shell only checks whether parameter is set or not.
The following parameters are automatically set by the Korn Shell:
# The number of positional parameters in decimal.
Flags supplied to the Korn Shell on invocation or
by the set command.
? The decimal value returned by the last executed
1
command.
$ The process number of this shell.
The last argument of the previous command.
The process number of the last background command
invoked.
PPID The process number of the parent of the shell.
PWD The present working directory set by the cd command.
RANDOM
Each time this parameter is referenced, a random
integer is generated. The sequence of random
numbers can be initialized by assigning a numeric
value to RANDOM.
REPLY
This parameter is set by the select statement and
by the read special command when no arguments
are supplied.
The following parameters are used by the Korn shell:
CDPATH
the search path for the cd command.
COLUMNS
If this variable is set, the value is used to define
the width of the edit window for the shell edit �
modes and for printing select lists.
EDITOR
If the value of either of these variables ends in
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