Ring/Lessons/System Functions

System Functions In this chapter we are going to learn about the system functions System() Get() IsMSDOS() IsWindows() IsWindows64() IsUnix() IsMacOSX() IsLinux() IsFreeBSD() IsAndroid() Windowsnl() Get Command Line Arguments Get Active Source File Name System() Function We can execute system commands using the system() function Syntax: System(cCommand) Example: System("myapp.exe") # Run myapp.exe System("ls") # print list of files Get() Function We can get environment variables using the Get() function Syntax: Get(cVariable) Example: see get("path") # print system path information IsMSDOS() We can check if the operating system is MSDOS or not using the IsMSDOS() function Syntax: IsMSDOS() ---> Returns 1 if the operating system is MS-DOS, Returns 0 if it's not IsWindows() We can check if the operating system is Windows or not using the IsWindows() function Syntax: IsWindows() ---> Returns 1 if the operating system is Windows, Returns 0 if it's not IsWindows64() We can check if the operating system is Windows 64bit or not using the IsWindows64() function Syntax: IsWindows64() ---> Returns 1 if the operating system is Windows64, Returns 0 if it's not IsUnix() We can check if the operating system is Unix or not using the IsUnix() function Syntax: IsUnix() ---> Returns 1 if the operating system is Unix, Returns 0 if it's not IsMacOSX() We can check if the operating system is Mac OS X or not using the IsMacOSX() function Syntax: IsMacOSX() ---> Returns 1 if the operating system is Mac OS X, Returns 0 if it's not IsLinux() We can check if the operating system is Linux or not using the IsLinux() function Syntax: IsLinux() ---> Returns 1 if the operating system is Linux, Returns 0 if it's not IsFreeBSD() We can check if the operating system is FreeBSD or not using the IsFreeBSD() function Syntax: IsFreeBSD() ---> Returns 1 if the operating system is FreeBSD, Returns 0 if it's not IsAndroid() We can check if the operating system is Android or not using the IsAndroid() function Syntax: IsAndroid() ---> Returns 1 if the operating system is Android, Returns 0 if it's not Example see "IsMSDOS() --> " + ismsdos() + nl see "IsWindows() --> " + iswindows() + nl see "IsWindows64() --> " + iswindows64() + nl see "IsUnix() --> " + isunix() + nl see "IsMacOSX() --> " + ismacosx() + nl see "IsLinux() --> " + islinux() + nl see "IsFreeBSD() --> " + isfreebsd() + nl see "IsAndroid() --> " + isandroid() + nl Output: IsMSDOS() --> 0 IsWindows() --> 1 IsWindows64() --> 0 IsUnix() --> 0 IsMacOSX() --> 0 IsLinux() --> 0 IsFreeBSD() --> 0 IsAndroid() --> 0 Windowsnl() We can get the windows new line string using the Windowsnl() function. Syntax: WindowsNL() ---> Returns a string contains CR+LF = CHAR(13) + CHAR(10) Example: cStr = read("input.txt") if iswindows() cStr = substr(cStr,windowsnl(),nl) ok aList = str2list(cStr) # to do - list items processing using "for in" cStr = list2str(aList) if iswindows() cStr = substr(cStr,nl,windowsnl()) ok write("ouput.txt",cStr) Get Command Line Arguments We can get the command line arguments passed to the ring script using the sysargv variable. The sysargv variable is a list contains the command line parameters. Example see copy("=",30) + nl see "Command Line Parameters" + nl see "Size : " + len(sysargv) + nl see sysargv see copy("=",30) + nl nStart = sysargv[3] nEnd = sysargv[4] for x = nStart to nEnd see x + nl next Output b:\mahmoud\apps\ring>ring tests\syspara.ring 1 10 ============================== Command Line Parameters Size : 4 ring tests\syspara.ring 1 10 ============================== 1 2 3 4 5 6 7 8 9 10 Get Active Source File Name We can get the active source file name (*.ring) using the filename() function Syntax: filename() ---> String contains the active source file name. Example: see "Active Source File Name : " + filename() + nl Output: Active Source File Name : tests\filename.ring Example: if sysargv[2] = filename() see "I'm the main program file!" + nl # we can run tests here! else see "I'm a sub file in a program" + nl ok Ring programming language