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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.


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


Name Description
StdioException Thrown if I/O errors happen.


Name Description
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.


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

Enum values

Name Type Description
isFileHandle Indicates whether T is a file handle, i.e. the type is implicitly convertable to File or a pointer to a core.stdc.stdio.FILE.


Name Type Description
KeepTerminator std.typecons 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.