Differences

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--- storing_20structures_20in_20files [2024/01/12 22:23] – Added BBCSDL code richardrussell
+++ storing_20structures_20in_20files [2024/01/12 22:46] (current) – Add generic code (e.g. for BBCTTY) richardrussell
@@ Line 4: / Line 4: @@
 BB4W:
 <code bb4w>
-        SYS "WriteFile", @hfile%(file%), struct{}, DIM(struct{}), ^temp%, 0
+      SYS "WriteFile", @hfile%(file%), struct{}, DIM(struct{}), ^temp%, 0
 </code>
 BBCSDL:
 <code bb4w>
-        SYS "SDL_RWwrite", @hfile%(file%), struct{}, DIM(struct{}), 1
+      SYS "SDL_RWwrite", @hfile%(file%), struct{}, DIM(struct{}), 1
+</code>
+Generic (e.g. BBCTTY):
+<code bb4w>
+      DEF PROCwritestruct(F%, s{})
+      LOCAL s$ : PTR(s$)=s{} : !(^s$+4)=DIM(s{}) : BPUT#F%,s$; : !(^s$+4)=0
+      ENDPROC
 </code>
 Similarly to read an entire structure **struct{}** from the file opened on channel **file%** do the following:\\ \\
 BB4W:
 <code bb4w>
-        SYS "ReadFile", @hfile%(file%), struct{}, DIM(struct{}), ^temp%, 0
+      SYS "ReadFile", @hfile%(file%), struct{}, DIM(struct{}), ^temp%, 0
 </code>
 BBCSDL:
 <code bb4w>
-        SYS "SDL_RWread", @hfile%(file%), struct{}, DIM(struct{}), 1
+      SYS "SDL_RWread", @hfile%(file%), struct{}, DIM(struct{}), 1
+</code>
+Generic (e.g. BBCTTY):
+<code bb4w>
+      DEF PROCreadstruct(F%, s{})
+      LOCAL s$ : PTR(s$)=s{} : !(^s$+4)=DIM(s{}) : s$=GET$#F% BY LENs$ : !(^s$+4)=0
+      ENDPROC
 </code>
 It is best not to mix these statements with conventional BASIC file reads and writes, but if you do you must flush BASIC's file buffers before each of the API calls, as follows:\\ \\