Guardian Native C Library Calls Reference Manual (G06.28+, H06.04+)

Guardian Native C Library Calls (f) fgets(3)
NAME
fgets - Gets a string from a stream
LIBRARY
G-series native Guardian processes: $SYSTEM.SYSnn.ZCRTLSRL
G-series native OSS processes: /G/system/sysnn/zcrtlsrl
H-series native Guardian processes: $SYSTEM.ZDLLnnn.ZCRTLDLL
H-series OSS processes: /G/system/zdllnnn/zcrtldll
SYNOPSIS
#include <stdio.h>
char *fgets(
char *string,
int n,
FILE *stream);
PARAMETERS
string Points to a string to receive bytes.
n Specifies an upper bound on the number of bytes to read.
stream Points to the FILE structure of an open file.
DESCRIPTION
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 EOF (End-of-File) condition is encountered.
The string is then terminated with a NULL character.
RETURN VALUES
If the end of the file is encountered and no characters have been read, no characters are
transferred to string and a null pointer is returned. If a read error occurs, a null pointer is
returned. Otherwise, string is returned.
ERRORS
If any of the following conditions occur, the fgets() function sets errno to the corresponding
value:
[EAGAIN] The O_NONBLOCK flag is set for the underlying input stream and the process
would be delayed by the read operation.
[EBADF] The file descriptor underlying the input stream is not a valid file descriptor or is
not open for reading.
[EINTR] The read operation was interrupted by a signal which was caught and no data
was transferred.
[ENXIO] A request was made on a nonexistent device, or the request was outside the
capabilities of the device.
[EIO] 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.
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