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diff --git a/man7/glob.7 b/man7/glob.7 deleted file mode 100644 index 6217b2c3e..000000000 --- a/man7/glob.7 +++ /dev/null @@ -1,205 +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 (date) "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. -.P -These days there is also a library routine -.BR glob (3) -that will perform this function for a user program. -.P -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: -.P -A \[aq]?\[aq] (not between brackets) matches any single character. -.P -A \[aq]*\[aq] (not between brackets) matches any string, -including the empty string. -.P -.B "Character classes" -.P -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].) -.P -.B Ranges -.P -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], and \[aq]0\[aq], -since \[aq]/\[aq] cannot be matched.) -.P -.B Complementation -.P -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], \[aq]a\[aq], and \[aq]\-\[aq].) -.P -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.) -.P -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 -.P -.nf - xv \-wait 0 *.gif *.jpg -.fi -.P -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: -.P -.in +4n -.EX -shopt \-s nullglob -.EE -.in -.\" In Bash v1, by setting allow_null_glob_expansion=true -.P -(Similar problems occur elsewhere. -For example, where old scripts have -.P -.in +4n -.EX -rm \`find . \-name "*\[ti]"\` -.EE -.in -.P -new scripts require -.P -.in +4n -.EX -rm \-f nosuchfile \`find . \-name "*\[ti]"\` -.EE -.in -.P -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. -.P -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: -.P -(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. -.P -(iv) Named character classes, like -.P -.nf -[:alnum:] [:alpha:] [:blank:] [:cntrl:] -[:digit:] [:graph:] [:lower:] [:print:] -[:punct:] [:space:] [:upper:] [:xdigit:] -.fi -.P -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 \[aq]z\[aq] -in the alphabet. -These character classes are defined by the -.B LC_CTYPE -category -in the current locale. -.P -(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. -.P -(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) |