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Full Discussion: Help on for loop in bash
Top Forums Shell Programming and Scripting Help on for loop in bash Post 302975828 by Don Cragun on Sunday 19th of June 2016 04:25:36 PM
Old 06-19-2016
There are several things that seem strange in your script, but some of what I'm seeing may just be a nomenclature problem. You have a variable named pattern and you have shown us the code segment:
Code:
test $# -eq 0 && read pattern
for pattern in "$pattern"
do
  result=
  for dir in $dirpath
  do
    for file in $dir/$pattern

which (even ignoring the missing do and three done commands) can't possibly be what you want. If $pattern expands to a list of files or a list of pathnames, the first time through the loop started with:
Code:
for pattern in "$pattern"

will set pattern to be the entire list and you will never go through that loop more than once.

And, if $pattern contains any filename pattern special characters (e.g., ?, *, [list], etc.), they will not be expanded inside double quotes.

When you enter patterns on the command line when you invoke your script are the patterns quoted (so the shell doesn't perform pattern matching before invoking your script)? When you read patterns from standard input, are they really patterns or are they just pathnames of files?
Last edited by Don Cragun; 06-19-2016 at 06:23 PM.. Reason: Fix misleading statement.
 

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LEARN ABOUT ULTRIX

fnmatch

FNMATCH(3)						     Linux Programmer's Manual							FNMATCH(3)

NAME

       fnmatch - match filename or pathname

SYNOPSIS

       #include <fnmatch.h>

       int fnmatch(const char *pattern, const char *string, int flags);

DESCRIPTION

       The fnmatch() function checks whether the string argument matches the pattern argument, which is a shell wildcard pattern.

       The flags argument modifies the behavior; it is the bitwise OR of zero or more of the following flags:

       FNM_NOESCAPE
	      If this flag is set, treat backslash as an ordinary character, instead of an escape character.

       FNM_PATHNAME
	      If  this	flag  is  set,	match  a  slash  in  string only with a slash in pattern and not by an asterisk (*) or a question mark (?)
	      metacharacter, nor by a bracket expression ([]) containing a slash.

       FNM_PERIOD
	      If this flag is set, a leading period in string has to be matched exactly by a period in pattern.  A  period  is	considered  to	be
	      leading if it is the first character in string, or if both FNM_PATHNAME is set and the period immediately follows a slash.

       FNM_FILE_NAME
	      This is a GNU synonym for FNM_PATHNAME.

       FNM_LEADING_DIR
	      If  this	flag (a GNU extension) is set, the pattern is considered to be matched if it matches an initial segment of string which is
	      followed by a slash.  This flag is mainly for the internal use of glibc and is implemented only in certain cases.

       FNM_CASEFOLD
	      If this flag (a GNU extension) is set, the pattern is matched case-insensitively.

       FNM_EXTMATCH
	      If this flag (a GNU extension) is set, extended patterns are supported, as introduced by 'ksh' and now supported	by  other  shells.
	      The extended format is as follows, with pattern-list being a '|' separated list of patterns.

       '?(pattern-list)'
	      The pattern matches if zero or one occurrences of any of the patterns in the pattern-list match the input string.

       '*(pattern-list)'
	      The pattern matches if zero or more occurrences of any of the patterns in the pattern-list match the input string.

       '+(pattern-list)'
	      The pattern matches if one or more occurrences of any of the patterns in the pattern-list match the input string.

       '@(pattern-list)'
	      The pattern matches if exactly one occurrence of any of the patterns in the pattern-list match the input string.

       '!(pattern-list)'
	      The pattern matches if the input string cannot be matched with any of the patterns in the pattern-list.

RETURN VALUE

       Zero if string matches pattern, FNM_NOMATCH if there is no match or another nonzero value if there is an error.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       +----------+---------------+--------------------+
       |Interface | Attribute	  | Value	       |
       +----------+---------------+--------------------+
       |fnmatch() | Thread safety | MT-Safe env locale |
       +----------+---------------+--------------------+
CONFORMING TO

       POSIX.1-2001, POSIX.1-2008, POSIX.2.  The FNM_FILE_NAME, FNM_LEADING_DIR, and FNM_CASEFOLD flags are GNU extensions.

SEE ALSO

       sh(1), glob(3), scandir(3), wordexp(3), glob(7)

COLOPHON

       This  page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

GNU
								    2015-12-28								FNMATCH(3)
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