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Top Forums Shell Programming and Scripting Understanding regex behaviour when using quantifiers Post 302749477 by chidori on Friday 28th of December 2012 12:01:14 PM
Old 12-28-2012
Understanding regex behaviour when using quantifiers

Code:
# echo "Teest string" | sed 's/e*/=>replaced=</'
=>replaced<=Teest string

So, in the above code , sed replaces at the start. does that mean sed using the pattern e* settles to zero occurence ? Why sed was not able to replace Teest string.

Code:
# echo "Teest string" | sed 's/e*//g'
Tst string

How does it work when global flag turned on ?
 

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sfind(1)                                                            ShapeTools                                                            sfind(1)

NAME
sfind - shapeTools RMS recursively descend a system hierarchy SYNOPSIS
sfind [-subs | -comp] directory [command] DESCRIPTION
Sfind recursively descends the system hierarchy of a software system managed by the shapeTools Release Management System (shapeTools RMS). Sfind starts it's search from directory downwards. According to the shapeTools RMS conventions, directory must contain a Shapefile which lists the subsystems in the variable SUBSYSTEMS and the subsystem components in the variable COMPONENTS. Each subsystem is visited. If no command is specified, sfind echoes the pathnames of the subsystems it finds, or, if the option -comp is given, the pathnames of the components of each subsystem. When a command is given, it is executed in the directory of each subsystem. The string ``{}'' in command is replaced by the pathname of the subsystem or component. OPTIONS
-subs command is invoked for each subsystem. This is the default. ``{}'' in command is replaced by the pathname of the subsystem. -comp command is invoked for each component. ``{}'' in command is replaced by the pathname of the component. EXAMPLES
List all system components: sfind -comp ~/development Show the pathnames of all versionfiles: sfind ~/development echo -n {}/ ; shape -echo VERSIONFILE Echo identification of the last release of each subsystem: sfind ~/development vl -last -format '$__lastrelease$\n' `shape -echo VERSIONFILE` Necessary quoting to echo a pair of curly braces: sfind ~/development echo two \{\} braces SEE ALSO
find(1), sh(1), shape(1), shape_RMS(1), shape_tmpl(7) CAVEATS
Quoting of shell meta characters can be tough. BUGS
The program is slow because shape(1) is called at least once for each subsystem. When sfind is interrupted, usually shape(1) displays the message ``shape - interrupted'', which may be confusing. AUTHOR
Andreas.Lampen@cs.tu-berlin.de shape_RMS-1.15 Fri Jun 25 17:01:50 1993 sfind(1)
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