Netpbm subroutine library: pm_make_tmpfile_fd() function

# pm_make_tmpfile_fd()

Updated: 31 December 2007

## NAME

pm_make_tmpfile_fd() - create a temporary named file

## SYNOPSIS

    #include <netpbm/pm.h>

    pm_make_tmpfile(int *         fdP,
                    const char ** filenameP);

## EXAMPLE

This simple example creates a temporary file, writes "hello world" to it, then writes some search patterns to it, then uses it as input to grep:

    #include <netpbm/pm.h>

    int fd;
    const char * myfilename;

    pm_make_tmpfile_fd(&fdP, &myfilename);

    write(fd, "^account:\\s.*\n", 16);
    fprintf(fd, "^name:\\s.*\n", 13);

    close(fd);

    asprintfN(&grepCommand, "grep --file='%s' /tmp/infile >/tmp/outfile");

    system(grepCommand);

    strfree(grepCommand);

    unlink(myfilename);

    strfree(myfilename);

## DESCRIPTION

This library function is part of Netpbm.

pm_make_tmpfile_fd() is analogous to pm_make_tmpfile(). The only difference is that it opens the file as a low level file, as open() would, rather than as a stream, as fopen() would.

If you don't need to access the file by name, use pm_tmpfile_fd() instead, because it's cleaner. With pm_tmpfile_fd(), the operating system always deletes the temporary file when your program exits, if the program failed to clean up after itself.

## HISTORY

pm_tmpfile() was introduced in Netpbm 10.42 (March 2008).