std.stdio

Standard I/O functions that extend std.c.stdio. std.c.stdio is automatically imported when importing std.stdio.

Source:
std/stdio.d

class StdioException: object.Exception;

Thrown if I/O errors happen.

void writef(...);

Arguments are formatted per the format strings and written to stdout.

void writefln(...);

Same as writef, but a newline is appended to the output.

void fwritef(_iobuf* fp, ...);

Same as writef, but output is sent to the stream fp instead of stdout.

void fwritefln(_iobuf* fp, ...);

Same as writefln, but output is sent to the stream fp instead of stdout.

string readln(_iobuf* fp = stdin);

Read line from stream fp.

Returns:
null for end of file, char[] for line read from fp, including terminating '\n'

Params:

_iobuf* fp

input stream

Throws:
StdioException on error

Example:
Reads stdin and writes it to stdout.

import std.stdio;

int main()
{
    char[] buf;
    while ((buf = readln()) != null)
        writef("%s", buf);
    return 0;
}

size_t readln(_iobuf* fp, ref char[] buf); size_t readln(ref char[] buf);

Read line from stream fp and write it to buf[], including terminating '\n'.

This is often faster than readln(FILE*) because the buffer is reused each call. Note that reusing the buffer means that the previous contents of it need to be copied if needed.

Params:

_iobuf* fp	input stream
char[] buf	buffer used to store the resulting line data. buf is resized as necessary.

Returns:
0 for end of file, otherwise number of characters read

Throws:
StdioException on error

Example:
Reads stdin and writes it to stdout.

import std.stdio;

int main()
{
    char[] buf;
    while (readln(stdin, buf))
        writef("%s", buf);
    return 0;
}