z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

tcsh
/usr/source/s1/ls.c. The results of matches are sorted separately at a low level to
preserve this order, such as, like the following example, where ../{memo,*box}
might expand to ../memo ../box ../mbox. (Note that ’memo’ was not sorted with the
results of matching ’*box’.) It is not an error when this construct expands to files
which do not exist, but it is possible to get an error from a command to which the
expanded list is passed. This construct may be nested. As a special case the words
{, } and {} are passed undisturbed. The character ~ at the beginning of a filename
refers to home directories. Standing alone, i.e. ~, it expands to the invoker’s home
directory as reflected in the value of the home shell variable. When followed by a
name consisting of letters, digits and - (hyphen) characters the shell searches for a
user with that name and substitutes their home directory; thus ~ken might expand
to /usr/ken and ~ken/chmach to /usr/ken/chmach. If the character ~ is followed
by a character other than a letter or / or appears elsewhere than at the beginning of
a word, it is left undisturbed. A command like setenv MANPATH
/usr/man:/usr/local/man:~/lib/man does not, therefore, do home directory substitution
as one might hope. It is an error for a glob-pattern containing ’*’, ’?’, ’[’ or ’~’, with or
without ’^’, not to match any files. However, only one pattern in a list of
glob-patterns must match a file (so that, for example, rm *.a *.c *.o would fail only if
there were no files in the current directory ending in ’.a’, ’.c’, or ’.o’), and if the
nonomatch shell variable is set a pattern (or list of patterns) which matches nothing
is left unchanged instead of causing an error.
The noglob shell variable can be set to prevent filename substitution, and the
expand-glob editor command, normally bound to ^X-*, can be used to interactively
expand individual filename substitutions.
Directory stack substitution: The directory stack is a list of directories,
numbered from zero, used by the pushd, popd and dirs built-in commands for
tcsh. dirs can print, store in a file, restore and clear the directory stack at any time,
and the savedirs and dirsfile shell variables can be set to store the directory stack
automatically on logout and restore it on login. The dirstack shell variable can be
examined to see the directory stack and set to put arbitrary directories into the
directory stack.
The character = (equal) followed by one or more digits expands to an entry in the
directory stack. The special case =- expands to the last directory in the stack. For
example,
> dirs -v
0 /usr/bin
1 /usr/spool/uucp
2 /usr/accts/sys
> echo =1
/usr/spool/uucp
> echo =0/calendar
/usr/bin/calendar
> echo =-
/usr/accts/sys
The noglob and nonomatch shell variables and the expand-glob editor command
apply to directory stack as well as filename substitutions.
Other substitutions: There are several more transformations involving filenames,
not strictly related to the “Directory stack substitution,” but mentioned here for
completeness. Any filename may be expanded to a full path when the symlinks
variable is set to expand. Quoting prevents this expansion, and the normalize-path
editor command does it on demand. The normalize-command editor command
expands commands in PATH into full paths on demand. Finally, cd and pushd
644 z/OS V1R9.0 UNIX System Services Command Reference