HP-UX Reference (11i v3 07/02) - 1 User Commands A-M (vol 1)
k
ksh(1) ksh(1)
For example, if r is aliased to
fc -e -, typing r bad=good c re-executes the most recent command
that starts with the letter
c and replaces the first occurrence of the string
bad with the string good.
The history file will be trimmed when all of the following conditions occurs:
Its size is greater than four kilobytes.
The number of commands in it is more than
HISTSIZE.
The file has not been modified in the last ten minutes.
The user has write permission for the directory in which the history file resides.
If any one of the above conditions does not occur, the history file will not be trimmed. When the history file
is trimmed, the latest
HISTSIZE commands will be available in the history file.
Special Commands
The following simple-commands are executed in the shell process. They permit input/output redirection.
Unless otherwise indicated, file descriptor 1 is the default output location and the exit status, when there
are no syntax errors, is zero. Commands that are preceded by
% or %% are treated specially in the follow-
ing ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Certain errors cause a script that contains them to abort.
4. Words following a command preceded by %% that are in the format of a variable assignment are
expanded with the same rules as a variable assignment. This means that tilde substitution is per-
formed after the
= sign and word splitting and file name generation are not performed.
The special commands are list here:
%:[ arg ... ] The command only expands parameters. A zero exit code is returned.
%.file [ arg ... ]
Read and execute commands from file and return. The commands are executed in the
current shell environment. The search path specified by PATH is used to find the directory
containing file. If any arguments arg are given, they become the positional parameters.
Otherwise the positional parameters are unchanged. The exit status is the exit status of
the last command executed. It is not necessary that the execute permission bit be set for
file.
%% alias [-tx ][name[=value ] ... ]
alias with no arguments prints the list of aliases in the form name=value on standard
output. An alias is defined for each name whose value is given. A trailing space in value
causes the next word to be checked for alias substitution. The
-t option is used to set and
list tracked aliases. The value of a tracked alias is the full path name corresponding to the
given name. The value of a tracked alias becomes undefined when the value of
PATH is
reset, but the alias remains tracked. Without the
-t option, for each name in the argu-
ment list for which no value is given, the name and value of the alias is printed. The
-x
option is used to set or print exported aliases. An exported alias is defined across sub-shell
environments. Alias returns true unless a name is given for which no alias has been
defined.
bg [ job ... ] Puts the specified jobs into the background. The current job is put in the background if job
is unspecified. See Jobs for a description of the format of job.
% break [n ] Exit from the enclosing for, while, until,or select loop, if any. If n is specified,
break n levels.
% continue [n ]
Resume the next iteration of the enclosing for, while, until,or select loop. If n is
specified, resume at the n-th enclosing loop.
cd [ -L-P ][arg ]
cd old new This command can take either of two forms. In the first form it changes the current direc-
tory to arg.Ifarg is - the directory is changed to the previous directory. The -L option
(default) preserves logical naming when treating symbolic links. cd -L .. moves the
current directory one path component closer to the root directory. The -P option
preserves the physical path when treating symbolic links. cd -P .. changes the work-
ing directory to the parent directory of the current directory. The shell parameter HOME is
500 Hewlett-Packard Company − 12 − HP-UX 11i Version 3: February 2007