fgets
, fgetws
Get a string from a stream.
Syntax
char *fgets(
char *str,
int numChars,
FILE *stream
);
wchar_t *fgetws(
wchar_t *str,
int numChars,
FILE *stream
);
Parameters
str
Storage location for data.
numChars
Maximum number of characters to read.
stream
Pointer to FILE
structure.
Return value
Each of these functions returns str
. NULL
is returned to indicate an error or an end-of-file condition. Use feof
or ferror
to determine whether an error occurred. If str
or stream
is a null pointer, or numChars
is less than or equal to zero, this function invokes the invalid parameter handler, as described in Parameter validation. If execution is allowed to continue, errno
is set to EINVAL
and the function returns NULL
.
For more information about return codes, see errno
, _doserrno
, _sys_errlist
, and _sys_nerr
.
Remarks
The fgets
function reads a string from the input stream
argument and stores it in str
. fgets
reads characters from the current stream position to and including the first newline character, to the end of the stream, or until the number of characters read is equal to numChars
- 1, whichever comes first. The result stored in str
is appended with a null character. The newline character, if read, is included in the string.
fgetws
is a wide-character version of fgets
.
fgetws
reads the wide-character argument str
as a multibyte-character string or as a wide-character string when stream
is opened in text mode or binary mode, respectively. For more information about using text and binary modes in Unicode and multibyte stream-I/O, see Text and binary mode file I/O and Unicode stream I/O in text and binary modes.
By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.
Generic-text routine mappings
TCHAR.H routine |
_UNICODE and _MBCS not defined |
_MBCS defined |
_UNICODE defined |
---|---|---|---|
_fgetts |
fgets |
fgets |
fgetws |
Requirements
Function | Required header |
---|---|
fgets |
<stdio.h> |
fgetws |
<stdio.h> or <wchar.h> |
For more compatibility information, see Compatibility.
Example
// crt_fgets.c
// This program uses fgets to display
// the first line from a file.
#include <stdio.h>
int main( void )
{
FILE *stream;
char line[100];
if( fopen_s( &stream, "crt_fgets.txt", "r" ) == 0 )
{
if( fgets( line, 100, stream ) == NULL)
printf( "fgets error\numChars" );
else
printf( "%s", line);
fclose( stream );
}
}
Input: crt_fgets.txt
Line one.
Line two.
Output
Line one.