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Nested strtok function problem in C [duplicate]（2个答案）
6天前关闭。
所以，我使用了lexer，在所有的flex恶作剧之后，我得到了这个文本：

ISEP 1252 "ADDRESS"
"Name1" 1253 "INFORMATICA"
"Name2" 1254 "Boilerplate1"
"Name3" 1255 "Boilerplate2"
"Name4" 1256 "Boilerplate3"
"Name5" 1257 "Boilerplate4"
"Name6" 1258 "Boilerplate5"

并将其存储在yytext中，然后im继续使用strtok分离每行和该行的内容：

// get first line
char* line = strtok(yytext, "\n");
// get school name
char* schoolName = strtok(line, " \t");
// get school num students
int schoolNumStudents = atoi(strtok(NULL, " \t"));
// get school address inside the quotes
char* schoolAddress = strtok(NULL, "\"");

strcpy(schools[schoolCount].name, schoolName);
schools[schoolCount].numStudents = schoolNumStudents;
strcpy(schools[schoolCount].address, schoolAddress);
//print school[schoolCount]
printf("Escola: %s\n", schools[schoolCount].name);
printf("Num alunos: %d\n", schools[schoolCount].numStudents);
printf("Morada: %s\n", schools[schoolCount].address);

// get teachers
line = strtok(NULL, "\n");
while (line != NULL) {
    char* teacherName = strtok(line, "\"");
    int teacherExt = atoi(strtok(NULL, " \t"));
    char* teacherDepartment = strtok(NULL, "\"");

    schools[schoolCount].numTeachers++;
    if(schools[schoolCount].teachers == NULL) {
        schools[schoolCount].teachers = (struct Teacher*) malloc(sizeof(struct Teacher));
    }
    else {
        schools[schoolCount].teachers = (struct Teacher*) realloc(schools[schoolCount].teachers, sizeof(struct Teacher) * (schools[schoolCount].numTeachers));
    }

    printf("Nome: %s\n", teacherName);
    printf("Ext: %d\n", teacherExt);
    printf("Departamento: %s\n", teacherDepartment);
    line = strtok(NULL, "\n");
}

schoolCount++;

这里要看到的是，作为yytext，我提供的字符串，第二个strtok(NULL, "\n")返回NULL，而不是第二行。我是不是漏掉了什么？
PS：除了我提供的代码之外，没有任何与C相关的代码，代码块嵌套在lex规则中。
我试着把yytext的内容复制到一个不同的变量，因为strtok改变了变量，而yytext被保留给lex，这没有完成任何事情，我试着清除strtok缓冲区，然后在第二行重新尝试strtok，也没有工作。