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diff --git a/man7/glob.7 b/man7/glob.7 deleted file mode 100644 index ccf69ac9b3..0000000000 --- a/man7/glob.7 +++ /dev/null @@ -1,202 +0,0 @@ -.\" Copyright (c) 1998 Andries Brouwer -.\" -.\" SPDX-License-Identifier: GPL-2.0-or-later -.\" -.\" 2003-08-24 fix for / by John Kristoff + joey -.\" -.TH GLOB 7 2020-08-13 "Linux man-pages (unreleased)" -.SH NAME -glob \- globbing pathnames -.SH DESCRIPTION -Long ago, in UNIX\ V6, there was a program -.I /etc/glob -that would expand wildcard patterns. -Soon afterward this became a shell built-in. -.PP -These days there is also a library routine -.BR glob (3) -that will perform this function for a user program. -.PP -The rules are as follows (POSIX.2, 3.13). -.SS Wildcard matching -A string is a wildcard pattern if it contains one of the -characters \(aq?\(aq, \(aq*\(aq, or \(aq[\(aq. -Globbing is the operation -that expands a wildcard pattern into the list of pathnames -matching the pattern. -Matching is defined by: -.PP -A \(aq?\(aq (not between brackets) matches any single character. -.PP -A \(aq*\(aq (not between brackets) matches any string, -including the empty string. -.PP -.B "Character classes" -.PP -An expression "\fI[...]\fP" where the first character after the -leading \(aq[\(aq is not an \(aq!\(aq matches a single character, -namely any of the characters enclosed by the brackets. -The string enclosed by the brackets cannot be empty; -therefore \(aq]\(aq can be allowed between the brackets, provided -that it is the first character. -(Thus, "\fI[][!]\fP" matches the -three characters \(aq[\(aq, \(aq]\(aq, and \(aq!\(aq.) -.PP -.B Ranges -.PP -There is one special convention: -two characters separated by \(aq\-\(aq denote a range. -(Thus, "\fI[A\-Fa\-f0\-9]\fP" -is equivalent to "\fI[ABCDEFabcdef0123456789]\fP".) -One may include \(aq\-\(aq in its literal meaning by making it the -first or last character between the brackets. -(Thus, "\fI[]\-]\fP" matches just the two characters \(aq]\(aq and \(aq\-\(aq, -and "\fI[\-\-0]\fP" matches the -three characters \(aq\-\(aq, \(aq.\(aq, \(aq0\(aq, since \(aq/\(aq -cannot be matched.) -.PP -.B Complementation -.PP -An expression "\fI[!...]\fP" matches a single character, namely -any character that is not matched by the expression obtained -by removing the first \(aq!\(aq from it. -(Thus, "\fI[!]a\-]\fP" matches any -single character except \(aq]\(aq, \(aqa\(aq, and \(aq\-\(aq.) -.PP -One can remove the special meaning of \(aq?\(aq, \(aq*\(aq, and \(aq[\(aq by -preceding them by a backslash, or, in case this is part of -a shell command line, enclosing them in quotes. -Between brackets these characters stand for themselves. -Thus, "\fI[[?*\e]\fP" matches the -four characters \(aq[\(aq, \(aq?\(aq, \(aq*\(aq, and \(aq\e\(aq. -.SS Pathnames -Globbing is applied on each of the components of a pathname -separately. -A \(aq/\(aq in a pathname cannot be matched by a \(aq?\(aq or \(aq*\(aq -wildcard, or by a range like "\fI[.\-0]\fP". -A range containing an explicit \(aq/\(aq character is syntactically incorrect. -(POSIX requires that syntactically incorrect patterns are left unchanged.) -.PP -If a filename starts with a \(aq.\(aq, -this character must be matched explicitly. -(Thus, \fIrm\ *\fP will not remove .profile, and \fItar\ c\ *\fP will not -archive all your files; \fItar\ c\ .\fP is better.) -.SS Empty lists -The nice and simple rule given above: "expand a wildcard pattern -into the list of matching pathnames" was the original UNIX -definition. -It allowed one to have patterns that expand into -an empty list, as in -.PP -.nf - xv \-wait 0 *.gif *.jpg -.fi -.PP -where perhaps no *.gif files are present (and this is not -an error). -However, POSIX requires that a wildcard pattern is left -unchanged when it is syntactically incorrect, or the list of -matching pathnames is empty. -With -.I bash -one can force the classical behavior using this command: -.PP -.in +4n -.EX -shopt \-s nullglob -.EE -.in -.\" In Bash v1, by setting allow_null_glob_expansion=true -.PP -(Similar problems occur elsewhere. -For example, where old scripts have -.PP -.in +4n -.EX -rm \`find . \-name "*\(ti"\` -.EE -.in -.PP -new scripts require -.PP -.in +4n -.EX -rm \-f nosuchfile \`find . \-name "*\(ti"\` -.EE -.in -.PP -to avoid error messages from -.I rm -called with an empty argument list.) -.SH NOTES -.SS Regular expressions -Note that wildcard patterns are not regular expressions, -although they are a bit similar. -First of all, they match -filenames, rather than text, and secondly, the conventions -are not the same: for example, in a regular expression \(aq*\(aq means zero or -more copies of the preceding thing. -.PP -Now that regular expressions have bracket expressions where -the negation is indicated by a \(aq\(ha\(aq, POSIX has declared the -effect of a wildcard pattern "\fI[\(ha...]\fP" to be undefined. -.SS Character classes and internationalization -Of course ranges were originally meant to be ASCII ranges, -so that "\fI[\ \-%]\fP" stands for "\fI[\ !"#$%]\fP" and "\fI[a\-z]\fP" stands -for "any lowercase letter". -Some UNIX implementations generalized this so that a range X\-Y -stands for the set of characters with code between the codes for -X and for Y. -However, this requires the user to know the -character coding in use on the local system, and moreover, is -not convenient if the collating sequence for the local alphabet -differs from the ordering of the character codes. -Therefore, POSIX extended the bracket notation greatly, -both for wildcard patterns and for regular expressions. -In the above we saw three types of items that can occur in a bracket -expression: namely (i) the negation, (ii) explicit single characters, -and (iii) ranges. -POSIX specifies ranges in an internationally -more useful way and adds three more types: -.PP -(iii) Ranges X\-Y comprise all characters that fall between X -and Y (inclusive) in the current collating sequence as defined -by the -.B LC_COLLATE -category in the current locale. -.PP -(iv) Named character classes, like -.PP -.nf -[:alnum:] [:alpha:] [:blank:] [:cntrl:] -[:digit:] [:graph:] [:lower:] [:print:] -[:punct:] [:space:] [:upper:] [:xdigit:] -.fi -.PP -so that one can say "\fI[[:lower:]]\fP" instead of "\fI[a\-z]\fP", and have -things work in Denmark, too, where there are three letters past \(aqz\(aq -in the alphabet. -These character classes are defined by the -.B LC_CTYPE -category -in the current locale. -.PP -(v) Collating symbols, like "\fI[.ch.]\fP" or "\fI[.a-acute.]\fP", -where the string between "\fI[.\fP" and "\fI.]\fP" is a collating -element defined for the current locale. -Note that this may -be a multicharacter element. -.PP -(vi) Equivalence class expressions, like "\fI[=a=]\fP", -where the string between "\fI[=\fP" and "\fI=]\fP" is any collating -element from its equivalence class, as defined for the -current locale. -For example, "\fI[[=a=]]\fP" might be equivalent -to "\fI[a\('a\(`a\(:a\(^a]\fP", that is, -to "\fI[a[.a-acute.][.a-grave.][.a-umlaut.][.a-circumflex.]]\fP". -.SH SEE ALSO -.BR sh (1), -.BR fnmatch (3), -.BR glob (3), -.BR locale (7), -.BR regex (7) |