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Top Forums Shell Programming and Scripting Bash variable delayed expansion? Post 302436046 by pludi on Friday 9th of July 2010 04:55:39 AM
Old 07-09-2010
  1. To use the output of a command, use $(), or the older backticks `. Regular quotes won't work.
  2. Variables are used by prefixing them with a dollar symbol
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packingrules(4) 					     Kernel Interfaces Manual						   packingrules(4)

NAME
packingrules - packing rules file for cachefs DESCRIPTION
is a packing rules file for packingrules contains a list of directories and files that are to be packed. It also contains a list of direc- tories and files that are to be specifically excluded from packing. See cachefspack(1M). Many users choose to manually create the packing rules file and edit it by hand. Users can edit the packingrules (using any editor) to permanently change the packingrules file, or to gain access to more powerful options that are not available from the command line (such as the command). It is much easier to enter complex wildcard expressions by editing the packingrules file. Following is a description of the lines in a packing rules file. Blank lines and lines that begin with a pound sign are ignored. Lines can be continued by placing a backslash () immediately before the newline character. All other lines in the packingrules file have one of the following formats: This line identifies a directory (or pair of directories) under which files should be packed. At least one directory name must be specified. The arguments must be fully qualified path names and may include environment variables. This line enumerates a list of files and subdirectories beneath the current directory to be packed. This specification is recursive. That is, specifying the name of a directory automatically includes all files and subdirectories it contains. This line enumerates a list of files that are not to be packed. Regular expressions are permitted. There are important differences between the arguments to the and the statements. The arguments to statements can contain slashes and are interpreted as file names relative to the directories. The arguments to statements are simpler names or expressions that cannot contain slashes. An statement will not override a LIST statement. statements only exclude files that are found beneath listed directories. If the first name argument to a or an statement begins with an exclamation point the remainder of the statement will be executed as a com- mand that will be run in the current directory. The output of the command will be treated as a list of newline separated file names to be packed command) or to be excluded from the packing list command). For the command, the resulting file names will be interpreted relative to the enclosing directory. Blanks can be embedded in an argument by escaping them with a backslash () or enclosing the argument in double quotes (` " '). Double quotes can be passed in arguments by escaping the double quotes with a backslash (). lines only apply to the statement that precedes them. lines can appear before any statement (in which case they apply to all or after a statement (in which case they only apply to the that precedes them). Any number of these statements can occur in any combinations. The order is not important. EXAMPLES
The use of these statements is illustrated in the following packing rules file. # # Ignore junk files. # IGNORE core *.o *.bak *% # # Pack everything in the work subdirectory and in a few # favorite mailboxes. # BASE /net/bigserver/export/home/myname LIST work LIST m/incoming LIST m/action LIST m/pending # # Pack two important project directories but skip # all postscript output. # BASE /net/bigserver/export/projects $HOME/projects LIST poindexter epiphany IGNORE *.ps # # Pack the foonly package. # BASE /net/bigserver/opt/foonly /opt/foonly LIST !cat .packinglist # # Also pack the latest executables for the standard # build environment. # BASE /net/bigserver/export/buildenv $HOME/buildenv LIST !find . -type f -a -perm -111 -a -print AUTHOR
was developed by Sun Microsystems, Inc. SEE ALSO
cachefspack(1M). packingrules(4)
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