Linux的奇怪错误记录

1. error: ‘for’ loop initial declarations are only allowed in C99 mode
   for(int i = 0; i < 31; i++){

note提示里面已有解决方法
note: use option -std=c99 or -std=gnu99 to compile your code

所以gcc只需要添加参数: 

	gcc -std=c99 target.c
	
其他版本c11:

	gcc -std=c1x
	gcc -std=c11

	gcc --version  //查看版本

---

2. error: unknown type name ‘sigset_t’
   
   warning: implicit declaration of function ‘sigemptyset’ [-Wimplicit-function-declaration]
   
   error: ‘SIG_BLOCK’ undeclared (first use in this function)

解决方法:

	gcc -std=gnu99 target.c
	

3. man文档不全

下载:

	yum install man-pages

其他命令不全:

	yum -y install gdb
	yum -y install tree