"fgets()" is a standard library function in C Language used for reading a line of text from a file or from the standard input (keyboard).
It reads characters from the specified input stream up to and including a newline character ('\n') or until the specified number of characters is read.
`fgets()` returns a pointer to the read string if successful, or NULL if an error occurs or if the end-of-file (EOF) is reached before any characters are read.
Line Input: It enables us to read entire lines of text from files or input streams, making it suitable for processing text-based data.
Buffer Management: It automatically appends a null character ('\0') to the end of the string it reads, making it safe to use with C strings.
char *fgets(char *str, int n, FILE *stream);
"str": Pointer to a character array where the line of text will be stored.
"n": Maximum number of characters to read, including the null terminator ('\0').
"stream": Pointer to a "FILE" object that identifies the input stream.
The "fgets()" function returns str if successful, or "NULL" if an error occurs or if the end of the file is reached before any characters are read.
Reads lines of text from the standard input (keyboard) and prints them back:
#include <stdio.h>
int main() {
char line[100]; // Assuming lines are no longer than 99 characters
printf("Enter lines of text (Ctrl+D to end):\n");
// Read lines from standard input until Ctrl+D (EOF) is encountered
while (fgets(line, sizeof(line), stdin) != NULL) {
// Print the line read
printf("You entered: %s", line);
}
return 0;
}
#include <stdio.h>
int main() {
char line[100]; // Assuming lines are no longer than 99 characters
printf("Enter lines of text (Ctrl+D to end):\n");
// Read lines from standard input until Ctrl+D (EOF) is encountered
while (fgets(line, sizeof(line), stdin) != NULL) {
// Print the line read
printf("You entered: %s", line);
}
return 0;
}
Reads lines of text from a file and prints them:
#include <stdio.h>
#include <string.h>
int main() {
FILE *file;
char line[100]; // Assuming lines are no longer than 99 characters
char *token;
// Open the file in read mode
file = fopen("example.txt", "r");
// Check if file opened successfully
if (file == NULL) {
perror("Error opening file");
return 1;
}
// Read lines from the file until EOF is encountered
while (fgets(line, sizeof(line), file) != NULL) {
// Tokenize the line by whitespace and process each token
token = strtok(line, " \t\n");
while (token != NULL) {
// Print each token
printf("Token: %s\n", token);
// Get the next token
token = strtok(NULL, " \t\n");
}
}
// Close the file
fclose(file);
return 0;
}
Process each line read using "fgets()".
"fgets()" can be used to read lines of text from standard input or files, allowing for processing and manipulation of the text data.