I've been experimenting with cgo these days to avoid writing C code. I have some shared libraries from C which I want to use in the go programs. So I was trying the passing pointer to C function from Go and got a panic! So let the code do the talking below is the code I used.
#ifndef __POINTER_H__
#define __POINTER_H__
| package main | |
| /* | |
| #include "pointer.h" | |
| */ | |
| import "C" | |
| import "fmt" | |
| type SStruct struct { |
| #include <string.h> | |
| #include "pointer.h" | |
| void GetSampleStruct(SampleStruct *t){ | |
| SampleStruct temp = {1,2,3.0}; | |
| memcpy(t, &temp, sizeof(SampleStruct)); | |
| return; | |
| } |
| #ifndef __POINTER_H__ | |
| #define __POINTER_H__ | |
| typedef struct { | |
| int a; | |
| int b; | |
| float c; | |
| } SampleStruct; |
| (import [os [popen]] | |
| [os.path [exists]] | |
| [sys] | |
| [re]) | |
| (defun get-font-metadata [ fontfile] | |
| "Given the font file function checks for its existence then runs the | |
| otfinfo tool from lcdf-typetools package to extract metadata | |
| information and returns the parsed dict." | |
| (if (not (exists fontfile)) |
| CFLAGS := -Wall -m32 -march=i386 -g -Iinclude1 -Iinclude2 | |
| LDFLAGS := -Llibrary-dir1 -Llibrary-dir2 | |
| FIRST_BINARY_SRC := FirstBinary.c | |
| FIRST_BINARY_OBJ := $(FIRST_BINARY_SRC:.c=.o) | |
| FIRST_BINARY := FirstBinary | |
| SECOND_BINARY_SRC := SecondBinary.c | |
| SECOND_BINARY_OBJS := $(SECOND_BINARY_SRC:.c=.o) | |
| SECOND_BINARY := SecondBinary |
| (import [glob [glob]] | |
| [os.path [expanduser]]) | |
| (defmacro pattern-glob [folder pattern] | |
| (quasiquote ( | |
| (let [[folderpath (expanduser (unquote folder))]] | |
| (if (not (.endswith folderpath "/")) | |
| (setv folderpath (+ folderpath "/"))) | |
| (fn [] (glob (+ folderpath | |
| (unquote pattern)))))))) |
| package main | |
| import ( | |
| "fmt" | |
| ) | |
| func main() { | |
| normalString := "ವಾಸುದೇವ" | |
| backquotedString := `ವಾಸುದೇವ` |
| -*- mode: compilation; default-directory: "c:/Users/invakam2/Documents/Workspace/Go/src/" -*- | |
| Compilation started at Tue Aug 13 13:57:59 | |
| go run test_strings.go | |
| Len of normalString 21 | |
| len of backquotedString 21 | |
| Normal string with range operator yields following: | |
| Unicode value: cb5, rendered value: ವ | |
| Unicode value: cbe, rendered value: ಾ | |
| Unicode value: cb8, rendered value: ಸ |
| /* Exercise: Loops and Functions #43 */ | |
| package main | |
| import ( | |
| "fmt" | |
| "math" | |
| ) | |
| func Sqrt(x float64) float64 { | |
| z := float64(2.) |