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Module std.stdio

Standard I/O functions that extend core.stdc.stdio. core.stdc.stdio is publically imported when importing std.stdio.


chunks(f, size) Iterates through a file a chunk at a time by using foreach.
openNetwork(host, port) Experimental network access via the File interface
popen(name, mode) Convenience function that forwards to core.sys.posix.stdio.popen with appropriately-constructed C-style strings.
readf(args) Reads formatted data from stdin using formattedRead.
readln(terminator) Read line from stdin.
readln(buf, terminator) Read line from stdin and write it to buf[], including terminating character.
toFile(data, fileName) Writes an array or range to a file. Shorthand for data.copy(File(fileName, "wb").lockingBinaryWriter). Similar to write, strings are written as-is, rather than encoded according to the File's orientation.
write(args) For each argument arg in args, format the argument (using to) and write the resulting string to args[0]. A call without any arguments will fail to compile.
writef(args) Writes formatted data to standard output (without a trailing newline).
writefln(args) Equivalent to writef(fmt, args, '\n').
writeln(args) Equivalent to write(args, '\n'). Calling writeln without arguments is valid and just prints a newline to the standard output.


StdioException Thrown if I/O errors happen.


File Encapsulates a FILE*. Generally D does not attempt to provide thin wrappers over equivalent functions in the C standard library, but manipulating FILE* values directly is unsafe and error-prone in many ways. The File type ensures safe manipulation, automatic file closing, and a lot of convenience.
lines Iterates through the lines of a file by using foreach.


LockType Used to specify the lock type for File.lock and File.tryLock.

Manifest constants

isFileHandle Indicates whether T is a file handle, i.e. the type is implicitly convertable to File or a pointer to a FILE.


KeepTerminator Flag!("keepTerminator") If flag KeepTerminator is set to KeepTerminator.yes, then the delimiter is included in the strings returned.
stderr The standard error stream.
stdin The standard input stream.
stdout The standard output stream.


Walter Bright, Andrei Alexandrescu, Alex Rønne Petersen


Boost License 1.0.