Rosetta Stone

Introduction

Often, people new to a programming language/library have trouble mapping the things they know how to do in other environments to the new environments.

It can be handy to have a sort of "Rosetta stone" that roughly translates tasks from one environment/language into another.

Programming languages

If you have experience in other programming languages (such as C++, Visual Basic), there are some Rosetta stone web pages that might help you. As FreePascal/Lazarus syntax and library is fairly consistent with Delphi's, sites that "translate" to Delphi are also a valuable resource.

Some useful pages:

• http://mc-computing.com/Languages/ This page has some explanation of the concepts involved
• http://rosettacode.org/wiki/Category:Pascal A huge amount of languages, even esoteric, and tasks make this site special

Operating systems

If you know how to do something in an operating system, chances are you can do the same using FPC/Lazarus.

The table below gives a rough mapping of some tasks:

Windows/DOS	Unix/Linux	Description	FreePascal/Lazarus
copy	cp	Copy file	Lazarus fileutil.copyfile; roll your own with filestreams
date /t	date	Show current date	sysutils.now (date/time); sysutils.date (date); sysutils.time (time)
del, erase	rm, rm -f	Delete file	sysutils.deletefile, erase
deltree, rmdir /s	rm -r,rm -rf	Remove directories with subdirectories	Lazarus fileutil.deletedirectory
dir	ls	Find files in a directory	Lazarus FindAllFiles
diskpart list volume	mount	Show partitions/volumes/drives on a computer	Windows: see Windows_Programming_Tips#Listing_all_available_drives Linux: see Linux_Programming_Tips#Get_the_list_of_mounted_partitions Unix: you'll have to parse some files (e.g. /etc/mtab) yourself, depending on Unix flavour; see Forum post
find	grep	Search for a text/string	Several options, including the pos, ansipos. Regular expression support is provided by the RegExpr unit.
ldifde	ldapsearch	Search through Active Directory/LDAP	Use Synapse ldapsend unit to work with LDAP queries; see e.g. example code on Leonardo Ramé's blog
mkdir	mkdir	Create directory	mkdir; forcedirectories (creates entire path, if necessary)
move	mv	Move file to another directory	Within partition/disk: sysutils.renamefile; otherwise copy and delete original
rename, ren	mv	Rename file	sysutils.renamefile (can also "move" a file between directories, but only on same partition/disk
shutdown	shutdown	Shut down computer	?
wget, curl	wget, curl	Download file from HTTP/FTP	Multiple options, e.g. use synapse httpsend or ftpsend units
?	which	Search for executable in path	Lazarus fileutil.FindDefaultExecutablePath