fgets

Reads at most count - 1 characters from the given file stream and stores them in the character array pointed to by str . Parsing stops if a newline character is found (in which case str will contain that newline character) or if end-of-file occurs. If bytes are read and no errors occur, writes a null character at the position immediately after the last character written to str .

Parameters

Return value

str on success, null pointer on failure.

If the end-of-file condition is encountered, sets the eof indicator on stream (see feof() ). This is only a failure if it causes no bytes to be read, in which case a null pointer is returned and the contents of the array pointed to by str are not altered (i.e. the first byte is not overwritten with a null character).

If the failure has been caused by some other error, sets the error indicator (see ferror() ) on stream . The contents of the array pointed to by str are indeterminate (it may not even be null-terminated).

Notes

POSIX additionally requires that fgets sets errno if a read error occurs.

Although the standard specification is unclear in the cases where count <= 1 , common implementations do

• if count < 1 , do nothing, report error,
• if count == 1 ,

• some implementations do nothing, report error,
• others read nothing, store zero in str [ 0 ] , report success.

Example

#include <stdio.h>
#include <stdlib.h>
 
int main(void)
{
    FILE* tmpf = tmpfile();
    fputs("Alan Turing\n", tmpf);
    fputs("John von Neumann\n", tmpf);
    fputs("Alonzo Church\n", tmpf);
 
    rewind(tmpf);
 
    char buf[8];
    while (fgets(buf, sizeof buf, tmpf) != NULL)
          printf("\"%s\"\n", buf);
 
    if (feof(tmpf))
       puts("End of file reached");
}

"Alan Tu"
"ring
"
"John vo"
"n Neuma"
"nn
"
"Alonzo "
"Church
"
End of file reached

References

See also