04-13-2005
stdin
hi,
how does a program know whether some data are available from stdin?
I would like to make a program which could read its data from stdin
and _if_there_is_nothing_at_stdin_ from a file which name is given
as an argument. If there is nothing in stdin and no filename is given as
argument, the program should quit immediatly (not wait.)
I'm on Linux with gcc (g++ in fact.)
TIA if any idea.
Samuel
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LEARN ABOUT LINUX
git-hash-object
GIT-HASH-OBJECT(1) Git Manual GIT-HASH-OBJECT(1)
NAME
git-hash-object - Compute object ID and optionally creates a blob from a file
SYNOPSIS
git hash-object [-t <type>] [-w] [--path=<file>|--no-filters] [--stdin] [--] <file>...
git hash-object [-t <type>] [-w] --stdin-paths [--no-filters] < <list-of-paths>
DESCRIPTION
Computes the object ID value for an object with specified type with the contents of the named file (which can be outside of the work tree),
and optionally writes the resulting object into the object database. Reports its object ID to its standard output. This is used by git
cvsimport to update the index without modifying files in the work tree. When <type> is not specified, it defaults to "blob".
OPTIONS
-t <type>
Specify the type (default: "blob").
-w
Actually write the object into the object database.
--stdin
Read the object from standard input instead of from a file.
--stdin-paths
Read file names from stdin instead of from the command-line.
--path
Hash object as it were located at the given path. The location of file does not directly influence on the hash value, but path is used
to determine what Git filters should be applied to the object before it can be placed to the object database, and, as result of
applying filters, the actual blob put into the object database may differ from the given file. This option is mainly useful for hashing
temporary files located outside of the working directory or files read from stdin.
--no-filters
Hash the contents as is, ignoring any input filter that would have been chosen by the attributes mechanism, including the end-of-line
conversion. If the file is read from standard input then this is always implied, unless the --path option is given.
GIT
Part of the git(1) suite
Git 1.8.5.3 01/14/2014 GIT-HASH-OBJECT(1)