c - nl_langinfo() - too much information -


the function nl_langinfo(int_curr_symbol) returns pointer string constant of format:

$(three-letter-pseudoacronym) $(sign)$(symbol)

so in locale (en_gb.utf-8), "gbp -£". want first 3 letters, there way apart assigning nul character third element, or using strncpy()?

strcpy(int_curr_symbol, nl_langinfo(int_curr_symbol));  // "gbp -£" int_curr_symbol[3] = '\0';  // or  strncpy(int_curr_symbol, nl_langinfo(int_curr_symbol), 3));  // "gbp"

additionally, nl_langinfo(crncystr), returns sign , symbol, whereas symbol in needed. "-£" -> "£"

int_curr_symbol appears gnu extension. in stead, suggest localeconv() , int_curr_symbol field of struct lconv. posix specification field:

the international currency symbol applicable current locale. first 3 characters contain alphabetic international currency symbol in accordance specified in iso 4217:1995 standard. fourth character (immediately preceding null byte) character used separate international currency symbol monetary quantity.

as can see, supposed contain getting.

about second approach:

additionally, nl_langinfo(crncystr), returns sign , symbol, whereas symbol in needed. "-£" -> "£"

this because sign defines whether symbol placed before value (+), after value (-), or if should replace radix character (.). posix specification of langinfo.h:

local currency symbol, preceded '-' if symbol should appear before value, '+' if symbol should appear after value, or '.' if symbol should replace radix character. if local currency symbol empty string, implementations may return empty string ( "" ).

as method of obtaining part of string, suggest copying relevant part out of returned values own buffer right after call. have because structure , various pointers returned either of functions allocated , maintained c library.

the reason given posix nl_langinfo() returned values:

the application shall not modify string returned. pointer returned nl_langinfo() might invalidated or string content might overwritten subsequent call nl_langinfo() in thread or nl_langinfo_l() in same thread or initial thread, subsequent calls setlocale() category corresponding category of item (see ) or category lc_all, or subsequent calls uselocale() change category corresponding category of item. pointer returned nl_langinfo_l() might invalidated or string content might overwritten subsequent call nl_langinfo_l() in same thread or nl_langinfo() in thread, or subsequent calls freelocale() or newlocale() free or modify locale object passed nl_langinfo_l().

and here similar reason given localeconv():

the localeconv() function shall return pointer filled-in object. application shall not modify structure return value points, nor storage areas pointed pointers within structure. returned pointer, , pointers within structure, might invalidated or structure or storage areas might overwritten subsequent call localeconv(). in addition, returned pointer, , pointers within structure, might invalidated or structure or storage areas might overwritten subsequent calls setlocale() categories lc_all, lc_monetary, or lc_numeric, or calls uselocale() change categories lc_monetary or lc_numeric.


Comments

Post a Comment

Popular posts from this blog

c++ - CryptStringToBinary API behavior -

i seeing strange behavior cryptstringtobinary cryptography api. please see below code (config: x64 debug): #include "stdafx.h" #include <windows.h> #include <strsafe.h> #include <iostream> #include <exception> void main() { dword dwskip; dword dwflags; dword dwdatalen; //lpcwstr pszinput = l"jaaaaaecaaadzgaaakqaagdnnl1l56bwgfjdgr3rpxtqqqn6daw3usv2emkjym4t"; //this works fine lpcwstr pszinput = l"mytest"; //doesnt work, api returns false,error code 0x0000000d // determine size of byte array , allocate memory. if(! cryptstringtobinary( pszinput, _tcslen( pszinput ) + 1, crypt_string_base64, null, &dwdatalen, &dwskip, &dwflags ) ) { dword dw = getlasterror(); //0x0000000d: data invalid throw std::exception( "error computing byte length." ); } byte *pbytebyte = null; try { ...
Read more

java.util.scanner - How to read and add only numbers to array from a text file -

i'm learning java , have question regarding reading file want read numbers file contains strings well. here example of file: 66.56 "3 java 3-43 5-42 2.1 1 and here coding: public class test { public static void main (string [] args){ if (0 < args.length) { file x = new file(args[0]); try{ scanner in = new scanner( new fileinputstream(x)); arraylist<double> test = new arraylist<>(); while(in.hasnext()){ if(in.hasnextdouble()){ double f=in.nextdouble(); test.add(f);} else {in.next();} } catch(ioexception e) { system.err.println("exception during reading: " + e); } } my problem add 66.56,2.1 , 1 doesn't add 3 after "3 or ignores 3-43 , 5-42 can tell me how skip strings , add doubles here? thanks all said 3 ie; "3, 3-43 , 4-42 strings either u read string , split , check number @ " , - or put in space between characters , integers. jvm after compilation tre...
Read more

iphone - Three second countdown in cocos2d -

i trying have 3 second countdown display when level beat in game. did: -(void) gamesegmentbeat { [self pauseschedulerandactions]; // overlay game opaque background ccsprite *opaquebg = [ccsprite spritewithfile:@"background1.png"]; opaquebg.position = screencenter; [self addchild:opaquebg z:10000]; // these 3 labels 3 seconds cclabelttf *three = [cclabelttf labelwithstring:@"3" fontname:@"helvetica" fontsize:100]; three.position = ccp(screencenter.x, screencenter.y); cclabelttf *two = [cclabelttf labelwithstring:@"2" fontname:@"helvetica" fontsize:100]; two.position = ccp(screencenter.x, screencenter.y); cclabelttf *one = [cclabelttf labelwithstring:@"1" fontname:@"helvetica" fontsize:100]; one.position = ccp(screencenter.x, screencenter.y); // secondspast specified in update method secondspast = 0; if (secondspast == 1) { [self addchild:thr...
Read more