C与getline()斗争-不兼容的整数到指针转换

Question

我需要我的程序收集随机用户输入，以返回字符数为奇数或偶数(return ( strlen ( &raw_scrap ) % 2 ) ;)

我无法让getline()函数从char raw_scrap全局声明中正常工作。

以下是我收到的警告：

$clang geomant.c -o geomant.bin
geomant.c:61:12: warning: incompatible integer to pointer conversion passing 'char' to parameter of type 'char **' [-Wint-conversion]
        getline ( raw_scrap, sizeof(&raw_scrap), stdin ) ;
                  ^~~~~~~~~
/usr/include/stdio.h:239:36: note: passing argument to parameter here
ssize_t  getline(char ** __restrict, size_t * __restrict,
                                   ^
geomant.c:61:23: warning: incompatible integer to pointer conversion passing 'unsigned long' to parameter of type 'size_t *' (aka 'unsigned long *') [-Wint-conversion]
        getline ( raw_scrap, sizeof(&raw_scrap), stdin ) ;
                             ^~~~~~~~~~~~~~~~~~
/usr/include/stdio.h:239:57: note: passing argument to parameter here
ssize_t  getline(char ** __restrict, size_t * __restrict,
                                                        ^
2 warnings generated.

下面是我的完整代码(省略了用于紧凑/可读性的重复数组)：

/*****************************************/
/*     Geomant : a basic implementation  */
/*  of the geomanteia intended as a first*/
/*  C training project                   */
/*  copyright \xc2\xa9 Sylvain Saboua    */
/*  <sylvain ! saboua (|) free ! fr>     */
/*****************************************/

# include <stdlib.h>
# include <stdio.h>
# include <string.h>
# include <unistd.h>

char *body_parts[] = { "head", "neck", "body", "legs" } ;
char *mother_figures[] = { "1st", "2nd", "3rd", "4th" } ;

int n_figure ;
int n_bodypart ;

char raw_scrap ;
char *figures[15][4] = {
        // mothers
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},

        // daughters
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},

        // nieces
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},

        // witnesses & judge
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"},
        {"* *", "* *", "* *", "* *"}
} ;

/*

        "mantize" : input fuction

 This function gathers a string of user input
 and returns a 0 or 1 for the evenness or
 oddity of the number of characters. It is called
 in a sequence by the next function to generate
 the figures one by one.

*/

int mantize ( int n_bodypart, int n_figure ) {
        printf ( "Hold or repeatedly press a key or keys to generate the %s of the %s mother
, then press Enter:\n",
                body_parts[n_bodypart], mother_figures[n_figure] ) ;
        getline ( raw_scrap, sizeof(&raw_scrap), stdin ) ;
        return ( strlen ( &raw_scrap ) % 2 ) ;
}

/*

        "generate" fuction:

 This function takes the cast result (being 0 or 1,
 odd or even) and use it to generate
 all 15 figures, from the mothers down to the
 daughters, nieces, witnesses and judge.

*/

int generate(){

        // generating the mothers

        for ( n_figure = 0 ; n_figure < 4 ; n_figure++ ) {
                for ( n_bodypart = 0 ; n_bodypart < 4 ; n_bodypart++ ) {
                        figures[n_figure][n_bodypart] =
                        (0 == mantize(n_bodypart, n_figure)) ? "* *" : "*" ;
                }
        }

        //generating the four daughters from the four mothers

        figures[4][0] = figures[0][0] ;
        figures[4][1] = figures[1][0] ;
        figures[4][2] = figures[2][0] ;
        figures[4][3] = figures[3][0] ;

        figures[5][0] = figures[0][1] ;
        figures[5][1] = figures[1][1] ;
        figures[5][2] = figures[2][1] ;
        figures[5][3] = figures[3][1] ;

        figures[6][0] = figures[0][2] ;
        figures[6][1] = figures[1][2] ;
        figures[6][2] = figures[2][2] ;
        figures[6][3] = figures[3][2] ;

        figures[7][0] = figures[0][3] ;
        figures[7][1] = figures[1][3] ;
        figures[7][2] = figures[2][3] ;
        figures[7][3] = figures[3][3] ;

        // generating the nieces

        figures[8][0] = ( figures[0][0] == figures[1][0] ) ? "* *" : " * " ;
        figures[8][1] = ( figures[0][1] == figures[1][1] ) ? "* *" : " * " ;
        figures[8][2] = ( figures[0][2] == figures[1][2] ) ? "* *" : " * " ;
        figures[8][3] = ( figures[0][3] == figures[1][3] ) ? "* *" : " * " ;

        figures[9][0] = ( figures[2][0] == figures[3][0] ) ? "* *" : " * " ;
        figures[9][1] = ( figures[2][1] == figures[3][1] ) ? "* *" : " * " ;
        figures[9][2] = ( figures[2][2] == figures[3][2] ) ? "* *" : " * " ;
        figures[9][3] = ( figures[2][3] == figures[3][3] ) ? "* *" : " * " ;

        figures[10][0] = ( figures[4][0] == figures[5][0] ) ? "* *" : " * " ;
        figures[10][1] = ( figures[4][1] == figures[5][1] ) ? "* *" : " * " ;
        figures[10][2] = ( figures[4][2] == figures[5][2] ) ? "* *" : " * " ;
        figures[10][3] = ( figures[4][3] == figures[5][3] ) ? "* *" : " * " ;

        figures[11][0] = ( figures[6][0] == figures[7][0] ) ? "* *" : " * " ;
        figures[11][1] = ( figures[6][1] == figures[7][1] ) ? "* *" : " * " ;
        figures[11][2] = ( figures[6][2] == figures[7][2] ) ? "* *" : " * " ;
        figures[11][3] = ( figures[6][3] == figures[7][3] ) ? "* *" : " * " ;

        // generating the witnesses

        figures[12][0] = ( figures[8][0] == figures[9][0] ) ? "* *" : " * " ;
        figures[12][1] = ( figures[8][1] == figures[9][1] ) ? "* *" : " * " ;
        figures[12][2] = ( figures[8][2] == figures[9][2] ) ? "* *" : " * " ;
        figures[12][3] = ( figures[8][3] == figures[9][3] ) ? "* *" : " * " ;

        figures[13][0] = ( figures[10][0] == figures[11][0] ) ? "* *" : " * " ;
        figures[13][1] = ( figures[10][1] == figures[11][1] ) ? "* *" : " * " ;
        figures[13][2] = ( figures[10][2] == figures[11][2] ) ? "* *" : " * " ;
        figures[13][3] = ( figures[10][3] == figures[11][3] ) ? "* *" : " * " ;

        //generating the judge

        figures[14][0] = ( figures[12][0] == figures[13][0] ) ? "* *" : " * " ;
        figures[14][1] = ( figures[12][1] == figures[13][1] ) ? "* *" : " * " ;
        figures[14][2] = ( figures[12][2] == figures[13][2] ) ? "* *" : " * " ;
        figures[14][3] = ( figures[12][3] == figures[13][3] ) ? "* *" : " * " ;

        return *figures[14][3] ;

}


/*

        "display" function:

 This function will display onscreen the final
 geomantic Shield for the given divination.
 The "-" & "|" characters are used for separation
 while the dots are displayed using "*"

*/
int main(){

        generate();

        //printf(*figures);

        /*
        printf(" --- ")
        for i in .*
        return(*raw_scrap[3][3]);
        */

}

Answer 1

你在滥用getline()。您将传递一个char值作为getline()的第一个参数，而不是所需的char **指针到指针到char。

根据POSIX getline() documentation (特别注意描述部分的粗体第二段)：

概要

#包括 ssize_t getdelim(char **限制lineptr，size_t * ssize_t n，int分隔符，文件*限制流)；ssize_t getline(char **限制lineptr，size_t *限制n，文件*限制流)；

描述

getdelim()函数将从流中读取，直到遇到与分隔符字符匹配的字符为止。分隔符参数是int，应用程序应确保其值是一个字符，该字符可表示为终止读取进程的同等价值的unsigned char。如果分隔符参数有任何其他值，则行为未定义。

应用程序应确保*lineptr free() 是可以传递给free()函数的有效参数。如果*n 为非零，则应用程序应确保 *lineptr 至少指向大小为 *n 字节的对象，或者是 null 指针.。

如果*lineptr是null指针，或者*lineptr指向的对象大小不足，则对象的分配应像由malloc()分配一样，或者对象应重新分配，就像由realloc()重新分配一样，使对象足够大以容纳要写入的字符，包括终止NUL，而*n应设置为新的大小。如果分配了对象，或者重新分配操作移动了对象，则将更新*lineptr以指向新对象或新位置。读取的字符(包括任何分隔符)应存储在对象中，并在遇到分隔符或文件末尾时添加终止NUL。

getline()函数应与带有分隔符字符等于<newline>字符的getdelim()函数等效。

正确使用getline()看起来更像这样：

char *raw_scrap = NULL;
size_t raw_scrap_size = 0UL;
   .
   .
   .
        getline ( &raw_scrap, &raw_scrap_size, stdin ) ;

getline()读取整行输入--您必须更改程序以处理行，而不是单个的char输入。

请注意，raw_scrap必须是指向char的指针，该指针的地址必须传递给getline()，第二个参数是实际size_t 变量E 272的地址，而不是调用sizeof()而不是地址的常量结果。

还请注意，这些参数中包含的值必须符合POSIX标准中指出的限制。