understanding {%/*}/ Post: 302445609

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Top Forums UNIX for Dummies Questions & Answers understanding {%/*}/ Post 302445609 by vemana on Monday 16th of August 2010 10:19:47 AM

08-16-2010

Registered User

Thanks Raja,ygemici.It really helped in understanding whats going on.
Raja,I am working on modifying a script.As part of it I am trying to understand the fucntionality of each function.
Code is trying to get an alternate configuration if specified from the command line ($1).If not use which is already existing using ($0).Below is the snippet:

Code:

 X=$0
   MOD="${X%/*}/env.ksh"
        
   if [ "$1" != "" ]; then
        MOD="${X%/*}/$1"
        if [ -f $MOD ]; then
           echo "Using override configuration file: [$MOD]"
        else
           echo "ERROR: Specified override configuration file [$MOD] was not found"
           MOD="${X%/*}/env.ksh"
           echo "Using default configuration file [$MOD]"
        fi
   fi

   cd `dirname $X`
   dir=`pwd`


   if [ -a $MOD ]; then
        echo "Common Environment Found.  Loading [$MOD]."
           SCRIPT_TYPE="WEB"
        . $MOD
        echo "Common Environment Load Complete."
   else
        echo "Common Environment NOT fond.  Aborting."
        exit -1
   fi

vemana

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LEARN ABOUT SUNOS

print

print(1)							   User Commands							  print(1)

NAME

       print - shell built-in function to output characters to the screen or window

SYNOPSIS

   ksh
       print [ -Rnprsu [n]] [arg...]

DESCRIPTION

   ksh
       The shell output mechanism. With no flags or with flag - or -, the arguments are printed on standard output as described by echo(1).

OPTIONS

       The following options are supported:

       -n	       suppresses new-line from being added to the output.

       -R

       -r	       (raw  mode) ignore the escape conventions of echo. The -R option will print all subsequent arguments and options other than
		       -n.

       -p	       causes the arguments to be written onto the pipe of the process spawned with |& instead of standard output.

       -s	       causes the arguments to be written onto the history file instead of standard output.

       -u [ n ]        flag can be used to specify a one digit file descriptor unit number n on which the output will be placed. The default is 1.

EXIT STATUS

       The following exit values are returned:

       0	Successful operation.

       >0	Output file is not open for writing.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       echo(1), ksh(1), attributes(5)

SunOS 5.10							    15 Apr 1994 							  print(1)