shopt -s nullglob Post: 302254561

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Top Forums Shell Programming and Scripting shopt -s nullglob Post 302254561 by msb65 on Tuesday 4th of November 2008 05:53:14 PM

11-04-2008

Registered User

shopt -s nullglob

Hi,

I am using BASH. In a directory there are files that match either of the following 2 patterns: [AST]*.L1A_[GL]AC* or S*.L1A_MLAC*

I would like to write a script that will include a for loop, where for each file in the directory, a certain function will be performed. For example:

for FILE in [AST]*.L1A_[GL]AC* S*.L1A_MLAC*; do
echo $FILE
done

The content of the directory will be random, and there are 3 potential scenarios: 1) Files of both patterns exist in the directory, 2) Only files of the 1st pattern exist, 3) Only files of the 2nd pattern exist. The last two scenarios are problematic as one of the patterns won't be matched, resulting in my script behaving oddly.

- I believe the way around this is to use the shopt -s nullglob option. Does anyone have any other ideas?

- MAIN QUESTION: Where in the code should I put the shopt -s nullglob and shopt -u nullglob? Of course the shopt -s nullglob should be set immediately before the the beginning of the for loop. But, can the shopt -u nullglob be immediately after the beginning of the for loop (ie):

shopt -s nullglob
for FILE in [AST]*.L1A_[GL]AC* S*.L1A_MLAC*; do
shopt -u nullglob
echo $FILE
done

OR after the conclusion of the for loop (ie):

shopt -s nullglob
for FILE in [AST]*.L1A_[GL]AC* S*.L1A_MLAC*; do
echo $FILE
done
shopt -u nullglob

The reason I ask is because I will of course have more complicated code within the for loop, and only want the shopt nullglob command to affect the pattern matching when calling the for loop.

Thanks for your help.

Mike

msb65

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git-clean

GIT-CLEAN(1)							    Git Manual							      GIT-CLEAN(1)

NAME

       git-clean - Remove untracked files from the working tree

SYNOPSIS

       git clean [-d] [-f] [-i] [-n] [-q] [-e <pattern>] [-x | -X] [--] <path>...

DESCRIPTION

       Cleans the working tree by recursively removing files that are not under version control, starting from the current directory.

       Normally, only files unknown to Git are removed, but if the -x option is specified, ignored files are also removed. This can, for example,
       be useful to remove all build products.

       If any optional <path>... arguments are given, only those paths are affected.

OPTIONS

       -d
	   Remove untracked directories in addition to untracked files. If an untracked directory is managed by a different Git repository, it is
	   not removed by default. Use -f option twice if you really want to remove such a directory.

       -f, --force
	   If the Git configuration variable clean.requireForce is not set to false, git clean will refuse to delete files or directories unless
	   given -f, -n or -i. Git will refuse to delete directories with .git sub directory or file unless a second -f is given.

       -i, --interactive
	   Show what would be done and clean files interactively. See "Interactive mode" for details.

       -n, --dry-run
	   Don't actually remove anything, just show what would be done.

       -q, --quiet
	   Be quiet, only report errors, but not the files that are successfully removed.

       -e <pattern>, --exclude=<pattern>
	   In addition to those found in .gitignore (per directory) and $GIT_DIR/info/exclude, also consider these patterns to be in the set of
	   the ignore rules in effect.

       -x
	   Don't use the standard ignore rules read from .gitignore (per directory) and $GIT_DIR/info/exclude, but do still use the ignore rules
	   given with -e options. This allows removing all untracked files, including build products. This can be used (possibly in conjunction
	   with git reset) to create a pristine working directory to test a clean build.

       -X
	   Remove only files ignored by Git. This may be useful to rebuild everything from scratch, but keep manually created files.

INTERACTIVE MODE

       When the command enters the interactive mode, it shows the files and directories to be cleaned, and goes into its interactive command loop.

       The command loop shows the list of subcommands available, and gives a prompt "What now> ". In general, when the prompt ends with a single
       >, you can pick only one of the choices given and type return, like this:

	       *** Commands ***
		   1: clean		   2: filter by pattern    3: select by numbers
		   4: ask each		   5: quit		   6: help
	       What now> 1

       You also could say c or clean above as long as the choice is unique.

       The main command loop has 6 subcommands.

       clean
	   Start cleaning files and directories, and then quit.

       filter by pattern
	   This shows the files and directories to be deleted and issues an "Input ignore patterns>>" prompt. You can input space-separated
	   patterns to exclude files and directories from deletion. E.g. "*.c *.h" will excludes files end with ".c" and ".h" from deletion. When
	   you are satisfied with the filtered result, press ENTER (empty) back to the main menu.

       select by numbers
	   This shows the files and directories to be deleted and issues an "Select items to delete>>" prompt. When the prompt ends with double >>
	   like this, you can make more than one selection, concatenated with whitespace or comma. Also you can say ranges. E.g. "2-5 7,9" to
	   choose 2,3,4,5,7,9 from the list. If the second number in a range is omitted, all remaining items are selected. E.g. "7-" to choose
	   7,8,9 from the list. You can say * to choose everything. Also when you are satisfied with the filtered result, press ENTER (empty) back
	   to the main menu.

       ask each
	   This will start to clean, and you must confirm one by one in order to delete items. Please note that this action is not as efficient as
	   the above two actions.

       quit
	   This lets you quit without do cleaning.

       help
	   Show brief usage of interactive git-clean.

SEE ALSO

       gitignore(5)

GIT

       Part of the git(1) suite

Git 2.17.1							    10/05/2018							      GIT-CLEAN(1)