#include <stdio.h>

int pclose(FILE *stream);




IEEE Std 1003.1-2017


The pclose() function shall close a stream that was opened by popen(), wait for the command to terminate, and return the termination status of the process that was running the command language interpreter. However, if a call caused the termination status to be unavailable to pclose(), then pclose() shall return -1 with errno set to ECHILD to report this situation. This can happen if the application calls one of the following functions:

  • wait()

  • waitpid() with a pid argument less than or equal to 0 or equal to the process ID of the command line interpreter

  • Any other function not defined in POSIX.1-2017 that could do one of the above

In any case, pclose() shall not return before the child process created by popen() has terminated.

If the command language interpreter cannot be executed, the child termination status returned by pclose() shall be as if the command language interpreter terminated using exit(127) or _exit(127).

The pclose() function shall not affect the termination status of any child of the calling process other than the one created by popen() for the associated stream.

If the argument stream to pclose() is not a pointer to a stream created by popen(), the result of pclose() is undefined.

If a thread is canceled during execution of pclose(), the behavior is undefined.

Return value#

Upon successful return, pclose() shall return the termination status of the command language interpreter. Otherwise, pclose() shall return -1 and set errno to indicate the error.


The pclose() function shall fail if:

  • [ECHILD] - The status of the child process could not be obtained, as described above.



Known bugs#


See Also#

  1. Standard library functions

  2. Table of Contents