Function needs to be called based on its first character in a supplied string Post: 303037127

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Top Forums UNIX for Beginners Questions & Answers Function needs to be called based on its first character in a supplied string Post 303037127 by drysdalk on Wednesday 24th of July 2019 08:33:54 AM

07-24-2019

Registered User

Hi,

Assuming you're using Bash as your shell, this is the ideal situation for the case statement. Consider the following example:

Code:

$ cat data.txt
Jog
mog
cat
dog
jug
Man
$ cat script.sh
#!/bin/bash

function j
{
        echo "Function J has been called with the following parameter: $1"
        return
}

function m
{
        echo "Function M has been called with the following parameter: $1"
        return
}

while read parameter
do
        echo "Considering parameter "$parameter"..."

        case "$parameter" in
                J*|j*)
                        j "$parameter"
                        ;;
                M*|m*)
                        m "$parameter"
                        ;;
        esac
done < data.txt

$ ./script.sh
Considering parameter Jog...
Function J has been called with the following parameter: Jog
Considering parameter mog...
Function M has been called with the following parameter: mog
Considering parameter cat...
Considering parameter dog...
Considering parameter jug...
Function J has been called with the following parameter: jug
Considering parameter Man...
Function M has been called with the following parameter: Man
$

Here the script reads all the parameters one at a time from the file data.txt, and if they start with a lower- or upper-case J or M the appropriate function is called. If the parameter under consideration starts with any other character whatsoever, no function is called, and the script moves right on to the next parameter in the file, continuing in this manner until it reaches the end.

Hope this helps !

drysdalk

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LEARN ABOUT DEBIAN

gtkdoc-mktmpl

gtkdoc-mktmpl(1)					      General Commands Manual						  gtkdoc-mktmpl(1)

NAME

       gtkdoc-mktmpl --  GTK DocBook documentation generator.

SYNOPSIS

       gtkdoc-mktmpl [ See below ]

DESCRIPTION

       gtkdoc-mktmpl This creates or updates the template files which contain the manually-edited documentation. (A template is a simple text form
       which is filled in with the description of a function, macro, enum, or struct.  For functions  and  macros  it  also  contains  fields  for
       describing the parameters.)

       This script reads in the existing templates, found in tmpl/*.sgml, moves these files to tmpl/*.sgml.bak, and then recreates the .sgml files
       according to the structure given in the file MODULE-sections.txt.

       Any new templates added, or new function parameters, are marked with FIXME so you can do a grep to see which parts need updating.

       Any templates which are no longer used (i.e. they are remove from MODULE-sections.txt) are placed in the  file  tmpl/MODULE-unused.txt.	If
       they are included again later they are automatically copied back into position.	If you are certain that these templates will never be used
       again you can delete them from MODULE-unused.txt.

       Any parameters to functions which are no longer used are separated from the rest of the parameters with the line <!-- # Unused Parameters #
       -->.  It  may  be  that	the parameter name has just been changed, in which case you can copy the description to the parameter with the new
       name. You can delete the unused parameter descriptions when no longer needed.

EXAMPLE

       See /usr/share/doc/gtk-doc-tools/examples, for a makefile.am and a configure.in example file.

AUTHOR

       This manual page was written by Christian Marillat marillat@debian.org for the Debian GNU/Linux system (but may be used by others).

																  gtkdoc-mktmpl(1)

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