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was reading the Head first C book and stumbled across the author saying gets() to be a bad practice
gets()is a function that’s been around for a long time. But all you really need to know is that you really shouldn’t use it.
why is it considered a bad practice?
Consider
#include<stdio.h>
int main()
{
char buffer[100];
gets(buffer);
printf("The input is %s",buffer);
}
When user types input of length within 99 then there is no problem. But when user types more than 99 characters it tries to write into memory it doesn't own.
The worst thing is it causes abnormal behaviour and the program terminates without any information which leaves user baffled about the current situation
An alternative way is to use char *fgets(char *s, int size, FILE *stream); function
Update: As pointed by @pmg : gets() removes newline while fgets() retains the new line
gets is prone to buffer overruns (i.e. memory corruption etc).
fgets over comes this by having passing in the size of the buffer
来源：https://stackoverflow.com/questions/22419866/is-the-gets-string-function-in-c-considered-a-bad-practice