Function exec_cmd

src/engine/execunix.cpp:173–357

#define EXECCMD_PIPE_WRITE 1

void exec_cmd
(
    string const * command,
    int flags,
    ExecCmdCallback func,
    void * closure,
    LIST * shell
)
{
    struct sigaction ignore, saveintr, savequit;
    sigset_t chldmask, savemask;

    int const slot = get_free_cmdtab_slot();
    int out[ 2 ];
    int err[ 2 ];
    char const * argv[ MAXARGC + 1 ];  /* +1 for NULL */

    /* Initialize default shell. */
    static LIST * default_shell;
    if ( !default_shell )
        default_shell = list_push_back( list_new(
            object_new( "/bin/sh" ) ),
            object_new( "-c" ) );

    if ( list_empty( shell ) )
        shell = default_shell;

    /* Forumulate argv. If shell was defined, be prepared for % and ! subs.
     * Otherwise, use stock /bin/sh.
     */
    argv_from_shell( argv, shell, command->value, slot );

    if ( DEBUG_EXECCMD )
    {
        int i;
        out_printf( "Using shell: " );
        list_print( shell );
        out_printf( "\n" );
        for ( i = 0; argv[ i ]; ++i )
            out_printf( "    argv[%d] = '%s'\n", i, argv[ i ] );
    }

    /* Create pipes for collecting child output. */
    if ( pipe( out ) < 0 || ( globs.pipe_action && pipe( err ) < 0 ) )
    {
        perror( "pipe" );
        exit( EXITBAD );
    }

    /* Start the command */

    timestamp_current( &cmdtab[ slot ].start_dt );

    if ( 0 < globs.timeout )
    {
        /* Handle hung processes by manually tracking elapsed time and signal
         * process when time limit expires.
         */