gets, fgets - Get a string from a stream
Standard C Library (libc.so, libc.a)
Interfaces documented on this reference page conform to industry standards as follows:
gets(), fgets(): XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about industry standards and associated tags.
Points to a string to receive bytes. Specifies an upper bound on the number of bytes to read. Points to the FILE structure of an open file.
The gets() function reads bytes from the standard input stream, stdin, into the array pointed to by the string parameter. Data is read until a newline character is read or an end-of-file condition is encountered. If reading is stopped due to a newline character, the newline character is discarded and the string is terminated with a null byte.
The fgets() function reads bytes from the data pointed to by the stream parameter into the array pointed to by the string parameter. Data is read until n-1 bytes have been read, until a newline character is read and transferred to string, or until an end-of-file condition is encountered. The string is then terminated with a null byte.
The gets() function does not check the input for a maximum size. Consequently, if more bytes are entered than will fit in the space allocated for the string parameter, gets() will write beyond the end of the allocated space, producing indeterminate results. To avoid this condition, use fgets() instead of gets().
Upon successful completion, the gets() and fgets() functions return string. If the stream is at end-of-file, the end-of-file indicator for the stream is set and a null pointer is returned. If a read error occurs, the error indicator for the stream is set, a null pointer is returned, and errno is set to indicate the error.
The fgets() and gets() functions set errno to the specified value for the following conditions: The O_NONBLOCK flag is set for the underlying stream and the process would be delayed by the read operation. The file descriptor underlying the stream is not a valid file descriptor or is not open for reading. The read operation was interrupted by a signal which was caught and no data was transferred. The call is attempting to read from the process's controlling terminal and either the process is ignoring or blocking the SIGTTIN signal or the process group is orphaned. Insufficient memory is available for the operation. The device associated with stream does not exist.
Functions: clearerr(3), feof(3), ferror(3), fgetws(3), fileno(3), fopen(3), fputws(3), fread(3), getc(3), getwc(3), puts(3), scanf(3)
Standards: standards(5) delim off