When searching for the error, I found some solutions. Although I didn't use it, I would like to sort it out. I hope it can help you and make it easier for you to read it later.
Today’s error record:
Error, collect2: ld returned 1 exit status
Solution 1: Change gcc -o 22 22.c to gcc -O2 -Wall -o 22 22.c -lpthread
When creating threads under Linux today, the following errors will appear during compilation:
[root@linuxserver 807]# gcc -o 22 22.c
/tmp/cc21HcoW.o(.text+0x4c): In function `main':
: undefined reference to `pthread_create'
collect2: ld returned 1 exit status
The procedure is:
#include <unistd.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
void testthread(void)
{
printf("I am working.\n");
printf("I am stopping.\n");
pthread_exit(0);
}
int main(int argc,char *argv[])
{
int i=0;
pthread_t pid;
char *szP=NULL;
while(1)
{
i++;
pthread_create(&pid,NULL,(void *)testthread,(void *)&i);
printf("ok%d,pid=%d\n",i,pid);
sleep(5);
}
}
At this point, just change the compilation method
Change gcc -o 22 22.c to gcc -O2 -Wall -o 22 22.c -lpthread
The most important thing is -lpthread
According to the error
/tmp/cc21HcoW.o(.text+0x4c): In function `main':
: undefined reference to `pthread_create'
collect2: ld returned 1 exit status
It can be seen that the system cannot find the pthread_create function at the time of ld. That is to say, the compiler cannot find one of the functions using the library when link is available.
If pthread_create is not good enough, it can be found in pthread.so, so you need to add the -lpthread compilation parameter to tell the linker to use the pthread module when linking.
Solution 2: Close
There may also be a small reason: because the last running window is not closed, just close the last window and run it again.
Solution 3: Wrong function
During the search, I found that some students typed the main function as mian...
so you know
Note: Refer to the following link for Method 1:
https://www.cnblogs.com/aspirant/p/3840101.html
End:
Sharing is also a way to deepen your understanding of the problem again. It may not be comprehensive, but it is definitely useful and will continue to be improved later~