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POC #define string, Servname not supported for ai_socktype
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copied!<p>I am trying to write socket program in C. My entire code works fine when I do</p> <pre><code>#define PORT "3333" </code></pre> <p>but not </p> <pre><code>#define PORT getParameter("setting.ini","PORT") </code></pre> <p>Basically, the getParameter just opens the setting.ini file and read through, look for the variable and its value then return it. The only reason I am doing this is because I don't want the port number to be hardcoded in my code. I got:</p> <blockquote> <p>"Servname not supported for ai_socktype" </p> </blockquote> <p>I have no clue what causes this error. Any ideas? </p> <pre><code>#include <stdlib.h> #include <stdio.h> #include <string.h> char *substring(char* str, int start, int length) { char *newString = (char *)malloc(length * sizeof(char)+1); int i, x = 0; int end=start+length-1; for(i = start ; i <= end; i++) newString[x++] = str[i]; newString[x] = '\0'; return newString; } char *getParameter(char *fName, char *pName) { FILE *fr; char line[80]; int i; fr = fopen (fName, "r"); /* open the file for reading */ while(fgets(line, 80, fr) != NULL) { i = strcspn (line,"="); if(strcmp(pName,substring(line,0,i))==0){ char *value = substring(line,i+1,strlen(line)-i); fclose(fr); return value; } } fclose(fr); } int main(void){ char *PORT = getParameter("setting.ini","PORT"); const int BACKLOG = atoi(getParameter("setting.ini","BACKLOG")); printf("%s\n",PORT); printf("%d\n",BACKLOG); return 0; } </code></pre>

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