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--- checking_20if_20a_20library_20is_20installed [2018/03/31 13:19] – external edit 127.0.0.1
+++ checking_20if_20a_20library_20is_20installed [2024/01/05 00:22] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 =====Checking if a library is INSTALLed=====
-//by Jon Ripley, January 2006//\\ \\ //BBC BASIC for Windows// provides no built in function to check whether a library has been loaded into memory using the **INSTALL** command. \\ \\  The following routine **FN_IsInstalled(lib$)** implements a method to check if a library is currently **INSTALL**ed:\\ \\
+//by Jon Ripley, January 2006//\\ \\ //BBC BASIC for Windows// provides no built in function to check whether a library has been loaded into memory using the **INSTALL** command. \\ \\  The following routine **FN_IsInstalled(lib$)** implements a method to check if a library is currently **INSTALL**ed:\\ \\ <code bb4w>
         DEF FN_IsInstalled(lib$)
         IF ?HIMEM = 0 THEN = FALSE
@@ Line 18: / Line 18: @@
           ENDWHILE
         UNTIL (!P% AND &FFFFFF) = &FFFF00
-        = FALSE
+        = FALSE </code>
-\\  To check if a library is installed use code similar to the following:\\ \\
+\\  To check if a library is installed use code similar to the following:\\ \\ <code bb4w>
         IF FN_IsInstalled(@lib$+"WINLIB") THEN
           PRINT "WINLIB is installed."
         ELSE
           PRINT "WINLIB is not installed."
-        ENDIF
+        ENDIF </code>
 \\  To list all installed libraries call **FN_IsInstalled("-")**.\\ \\
 ===== Installing a library only once =====
-\\  When you [[http://www.bbcbasic.co.uk/bbcwin/manual/bbcwin5.html#install|INSTALL]] a library, //BBC BASIC for Windows// checks whether that library is already installed (version 5.91a or later only), however it performs a case-sensitive comparison of the supplied path/filename. It will reliably detect the **same** INSTALL statement being executed a second time, but not necessarily a **different** INSTALL statement which installs the same library but specifies it differently.\\ \\  Installing a library more than once is safe but wastes memory. If this is a concern, the following routine can be used instead of **INSTALL**:\\ \\
+\\  When you [[http://www.bbcbasic.co.uk/bbcwin/manual/bbcwin5.html#install|INSTALL]] a library, //BBC BASIC for Windows// checks whether that library is already installed (version 5.91a or later only), however it performs a case-sensitive comparison of the supplied path/filename. It will reliably detect the **same** INSTALL statement being executed a second time, but not necessarily a **different** INSTALL statement which installs the same library but specifies it differently.\\ \\  Installing a library more than once is safe but wastes memory. If this is a concern, the following routine can be used instead of **INSTALL**:\\ \\ <code bb4w>
         DEF PROC_InstallOnce(lib$)
         IF NOT FN_IsInstalled(lib$) THEN INSTALL lib$
-        ENDPROC
+        ENDPROC </code>