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Top Forums Shell Programming and Scripting How to execute the rest of the code after commenting multiple lines? Post 302154764 by drl on Tuesday 1st of January 2008 05:03:57 PM
Old 01-01-2008
Hi.

A few comments. First, there is a "quoted" string feature in the shells for HERE documents. The use prevents evaluation of everything up to the closing string, including unclosed quotes, variable issues, etc.

Second, ksh does a good job of diagnosing a missing, closing, matching HERE document string -- bash (2 & 3) simply stop.

A ksh example:
Code:
#!/usr/bin/env ksh

# @(#) s1       Demonstrate quick method to render code block inoperable.

set -o nounset
echo

debug=":"
debug="echo"

## The shebang using "env" line is designed for portability and
#  demonstrations. For higher security, use:
#
#  #!/bin/ksh -

## Use local command version for the commands in this demonstration.

echo "(Versions displayed with local utility \"version\")"
version >/dev/null 2>&1 && version ksh

echo
echo " Commands before commented-out block."

: <<'EOF'
garbage
junk
worthless
utterly without merit
" crud inside of double quotes "
' debris inside single quote '
" mess inside unmatched double-quotes
' detritus inside an unmatched single-quote pair
...
and so on.
EOF

echo
echo " Commands after  commented-out block."

echo
echo " Failed block quote due to unmatched HERE stings:"

echo
echo " Commands before commented-out block."

: <<'MISSING'
more junk
OOPS!

echo " Commands after  commented-out block."

exit 0

producing:
Code:
% ./s1

(Versions displayed with local utility "version")
pdksh 5.2.14 99/07/13.2

 Commands before commented-out block.

 Commands after  commented-out block.

 Failed block quote due to unmatched HERE stings:

 Commands before commented-out block.
./s1[53]: here document `MISSING' unclosed

I don't use ksh for reasons of availability (my shebangs almost always use simple "sh"), but in this case ksh is superior ... cheers, drl
 

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dfstab(4)							   File Formats 							 dfstab(4)

NAME
dfstab - file containing commands for sharing resources across a network DESCRIPTION
dfstab resides in directory /etc/dfs and contains commands for sharing resources across a network. dfstab gives a system administrator a uniform method of controlling the automatic sharing of local resources. Each line of the dfstab file consists of a share(1M) command. The dfstab file can be read by the shell to share all resources. System administrators can also prepare their own shell scripts to execute particular lines from dfstab. The contents of dfstab put into effect when the command shown below is run. See svcadm(1M). /usr/sbin/svcadm enable network/nfs/server SEE ALSO
share(1M), shareall(1M), sharemgr(1M), svcadm(1M) NOTES
Do not modify this file directly. This file is reconstructed and only maintained for backwards compatibility. Configuration lines could be lost. Use the sharemgr(1M) command for all share management. SunOS 5.11 15 Aug 2008 dfstab(4)
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