fgets

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: Considering i have a 100GB txt file containing millions of lines of text. How could i read this text file by block of lines using PHP? i can't use file_get_contents(); because the file is too large. fgets() also read the text line by line which will likely takes longer time to finish reading the whole file. If i'll be using fread($fp,5030) wherein '5030' is some length value for which it has to read. Would there be a case where it won't read the whole line(such as stop at the middle of the line) because it has reached the max length? 回答1: i

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I have a popen() function which executes "tail -f sometextfile". Aslong as there is data in the filestream obviously i can get the data through fgets(). Now, if no new data comes from tail, fgets() hangs. I tried ferror() and feof() to no avail. How can i make sure fgets() doesn't try to read data when nothing new is in the file stream? One of the suggestion was select(). Since this is for Windows Platform select doesn't seem to work as anonymous pipes do not seem to work for it (see this post ). 回答1: In Linux (or any Unix-y OS), you can

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: If I don't know how long the word is, I cannot write char m[6]; , The length of the word is maybe ten or twenty long. How can I use scanf to get input from the keyboard? #include <stdio.h> int main(void) { char m[6]; printf("please input a string with length=5\n"); scanf("%s",&m); printf("this is the string: %s\n", m); return 0; } please input a string with lenght=5 hello this is the string: hello 回答1: Enter while securing an area dynamically E.G. #include <stdio.h> #include <stdlib.h> char *inputString(FILE* fp, size_t size){ //The size is

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: This is how I've done it but I'm not sure this is the preferred idiom: FILE *fp = fopen(argv[0], "r"); // handle fopen() returning NULL while (!feof(fp)) { char buffer[80]; // statically allocated, may replace this later with some more sophisticated approach int num_chars = 0; for (int ch = fgetc(fp); ch != EOF && ch != '\n'; ch = fgetc()) { buffer[num_chars++] = ch; } // null-terminate the string buffer[num_chars] = '\0'; printf("%s\n", buffer); } Is this okay, any suggestions to improve this? 回答1: If you are not going to use fgets()

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: I am really new to C, and the reading files thing drives me crazy... I want read a file including name, born place and phone number, etc. All separated by tab The format might be like this: Bob Jason Los Angeles 33333333 Alice Wong Washington DC 111-333-222 So I create a struct to record it. typedef struct Person{ char name[20]; char address[30]; char phone[20]; } Person; I tried many ways to read this file into struct but it failed. I tired fread: read_file = fopen("read.txt", "r"); Person temp; fread(&temp, sizeof(Person), 100, read_file);

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: For my practice assignment I have to use either gets() or fgets(). I chose fgets() as its more secure. The first input is meant to be able to hold a maximum of 5 characters. So i gave the char array a size of 6 to accommodate the trailing '\0'. I found the fgets() issue of it adding a trailing '\n' when you press Enter (using stdin with fgets()) I done a bit of research and found a for loop to try and get rid of it. However, it doesnt seem to be working and i cant for the life of me figure out why. Its still skipping the next input when i

include <stdio.h> 函数 描述 参数 返回 char *gets(char *s); 从标准输入读入字符，并保存到s指定的内存空间，直到出现换行符或读到文件结尾为止 s：字符串首地址 成功：读入的字符串,失败：NULL char *fgets(char *s, int size, FILE *stream); 从stream指定的文件内读入字符，保存到s所指定的内存空间，直到出现换行字符、读到文件结尾或是已读了size - 1个字符为止，最后会自动加上字符 ‘\0’ 作为字符串结束。 s：字符串size：指定最大读取字符串的长度（size - 1）stream：文件指针，如果读键盘输入的字符串，固定写为stdin 成功：成功读取的字符串；读到文件尾或出错： NULL int puts(const char *s); 标准设备输出s字符串，在输出完成后自动输出一个’\n’。 s：字符串首地址 成功：非负数；失败：-1 int fputs(const char * str, FILE * stream); 将str所指定的字符串写入到stream指定的文件中， 字符串结束符 ‘\0’ 不写入文件。 str：字符串stream：文件指针，如果把字符串输出到屏幕，固定写为stdout 成功：0 失败：-1 gets(str)与scanf(“%s”,str)的区别： gets

Does fgets() always terminate the char buffer with \0 even if EOF is already reached? It looks like it does (it certainly does in the implementation presented in the ANSI K&R book), but I thought I would ask to be sure. I guess this question applies to other similar functions such as gets(). EDIT: I know that \0 is appended during "normal" circumstances, my question is targeted at EOF or error conditions. For example: FILE *fp; char b[128]; /* ... */ if (feof(fp)) { /* is \0 appended after EACH of these calls? */ fgets(b, 128, fp); fgets(b, 128, fp); fgets(b, 128, fp); } Never use gets!! 7.19

I understand the differences between fgets() and fgetss() but I don't get the difference between fgets() and fread() , can someone please clarify this subject? Which one is faster? Thanks! Pascal MARTIN fgets reads a line -- i.e. it will stop at a newline. fread reads raw data -- it will stop after a specified (or default) number of bytes, independently of any newline that might or might not be present. Speed is not a reason to use one over the other, as those two functions just don't do the same thing : If you want to read a line, from a text file, then use fgets If you want to read some data