tcdrain(3) — Linux manual page

tcdrain(3)               Library Functions Manual              tcdrain(3)

NAME         top

       tcdrain - block until output is transmitted

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <termios.h>

       int tcdrain(int fd);

DESCRIPTION         top

       tcdrain() waits until all output written to the object referred to
       by fd has been transmitted.

RETURN VALUE         top

       0      on success.

       -1     on failure and set errno to indicate the error.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ tcdrain()                            │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001.

SEE ALSO         top

       tcsendbreak(3), tcflush(3), tcflow(3), termios(7)

COLOPHON         top

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Linux man-pages 6.19            2026-07-02                     tcdrain(3)

Pages that refer to this page: FIONREAD(2const),  tcflow(3),  tcflush(3),  tcsendbreak(3),  signal-safety(7),  termios(7)

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