Linux Shell Scripting Cookbook - Third Edition

How it works...

The preceding image_help.sh script accepts these arguments:

• -source: This specifies the source directory of the images.
• -dest: This specifies the destination directory of the converted image files. If -dest is not specified, the destination directory will be the same as the source directory.
• -ext: This specifies the target file format for conversions.
• -percent: This specifies the percentage of scaling.
• -scale: This specifies the scaled width and height.
• Both the -percent and -scale parameters may not appear.
• The script starts by checking the number of command arguments. Either four, six, or eight parameters are valid.

The command line is parsed with a while loop and the case statement and values are assigned to appropriate ...