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Top Forums Shell Programming and Scripting Bash script to find comments in file Post 302926012 by Don Cragun on Thursday 20th of November 2014 06:50:39 PM
Old 11-20-2014
Don't tell us it "prompts me for more info"; show us the exact message that bash prints as a prompt.

When I save the following:
Code:
#!/bin/bash
found=0
n=1
while read -r line
do	# Look for comments...
	if [ "$line" != "${line#*#}" ]
	then	# Comment found, print line with line #...
		printf '%d\t%s\n' $n "$line"
		# Note that we found a comment...
		found=1
	fi
	# Increment line # for next line...
	n=$((n + 1))
done
# Print note if no comments found...
if [ ! $found ]
then	echo "No comments found."
fi

in myscript.bash, make it exeutable with:
Code:
chmod +x myscript.bash

and execute it with:
Code:
./myscript.bash < myscript.bash

(which reads itself as a file; not from data typed into the shell on standard input), I get the output:
Code:
1	#!/bin/bash
5	do	# Look for comments...
6	if [ "$line" != "${line#*#}" ]
7	then	# Comment found, print line with line #...
9	# Note that we found a comment...
12	# Increment line # for next line...
15	# Print note if no comments found.

which correctly shows all lines with comments, but has a false positive on line #6. It does not prompt for any more info.

As I said before: "Writing a full parser to find C or shell or some other language's comments accurately in bash is a non-trivial challenge." I'm not going to attempt to weed out the false positives this script will print for you on a forum like this.
This User Gave Thanks to Don Cragun For This Post:
 

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LIBBASH(7)							  libbash Manual							LIBBASH(7)

NAME
libbash -- A bash shared libraries package. DESCRIPTION
libbash is a package that enables bash dynamic-like shared libraries. Actually its a tool for managing bash scripts whose functions you may want to load and use in scripts of your own. It contains a 'dynamic loader' for the shared libraries ( ldbash(1)), a configuration tool (ldbashconfig(8)), and some libraries. Using ldbash(1) you are able to load loadable bash libraries, such as getopts(1) and hashstash(1). A bash shared library that can be loaded using ldbash(1) must answer 4 requirments: 1. It must be installed in $LIBBASH_PREFIX/lib/bash (default is /usr/lib/bash). 2. It must contain a line that begins with '#EXPORT='. That line will contain (after the '=') a list of functions that the library exports. I.e. all the function that will be usable after loading that library will be listed in that line. 3. It must contain a line that begins with '#REQUIRE='. That line will contain (after the '=') a list of bash libraries that are required for our library. I.e. every bash library that is in use in our bash library must be listed there. 4. The library must be listed (For more information, see ldbashconfig(8)). Basic guidelines for writing library of your own: 1. Be aware, that your library will be actually sourced. So, basically, it should contain (i.e define) only functions. 2. Try to declare all variables intended for internal use as local. 3. Global variables and functions that are intended for internal use (i.e are not defined in '#EXPORT=') should begin with: __<library_name>_ For example, internal function myfoosort of hashstash library should be named as __hashstash_myfoosort This helps to avoid conflicts in global name space when using libraries that come from different vendors. 4. See html manual for full version of this guide. AUTHORS
Hai Zaar <haizaar@haizaar.com> Gil Ran <ril@ran4.net> SEE ALSO
ldbash(1), ldbashconfig(8), getopts(1), hashstash(1) colors(1) messages(1) urlcoding(1) locks(1) Linux Epoch Linux
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