diff options
Diffstat (limited to 'generic/tclPipe.c')
| -rw-r--r-- | generic/tclPipe.c | 413 |
1 files changed, 205 insertions, 208 deletions
diff --git a/generic/tclPipe.c b/generic/tclPipe.c index d4a45cd..4238139 100644 --- a/generic/tclPipe.c +++ b/generic/tclPipe.c @@ -1,61 +1,58 @@ /* * tclPipe.c -- * - * This file contains the generic portion of the command channel - * driver as well as various utility routines used in managing - * subprocesses. + * This file contains the generic portion of the command channel driver + * as well as various utility routines used in managing subprocesses. * * Copyright (c) 1997 by Sun Microsystems, Inc. * - * See the file "license.terms" for information on usage and redistribution - * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tclPipe.c,v 1.10 2004/10/26 20:24:15 davygrvy Exp $ + * RCS: @(#) $Id: tclPipe.c,v 1.11 2005/07/21 14:38:50 dkf Exp $ */ #include "tclInt.h" /* - * A linked list of the following structures is used to keep track - * of child processes that have been detached but haven't exited - * yet, so we can make sure that they're properly "reaped" (officially - * waited for) and don't lie around as zombies cluttering the - * system. + * A linked list of the following structures is used to keep track of child + * processes that have been detached but haven't exited yet, so we can make + * sure that they're properly "reaped" (officially waited for) and don't lie + * around as zombies cluttering the system. */ typedef struct Detached { - Tcl_Pid pid; /* Id of process that's been detached - * but isn't known to have exited. */ - struct Detached *nextPtr; /* Next in list of all detached - * processes. */ + Tcl_Pid pid; /* Id of process that's been detached but + * isn't known to have exited. */ + struct Detached *nextPtr; /* Next in list of all detached processes. */ } Detached; -static Detached *detList = NULL; /* List of all detached proceses. */ -TCL_DECLARE_MUTEX(pipeMutex) /* Guard access to detList. */ +static Detached *detList = NULL;/* List of all detached proceses. */ +TCL_DECLARE_MUTEX(pipeMutex) /* Guard access to detList. */ /* - * Declarations for local procedures defined in this file: + * Declarations for local functions defined in this file: */ -static TclFile FileForRedirect _ANSI_ARGS_((Tcl_Interp *interp, - CONST char *spec, int atOk, CONST char *arg, - CONST char *nextArg, int flags, int *skipPtr, - int *closePtr, int *releasePtr)); +static TclFile FileForRedirect _ANSI_ARGS_((Tcl_Interp *interp, + CONST char *spec, int atOk, CONST char *arg, + CONST char *nextArg, int flags, int *skipPtr, + int *closePtr, int *releasePtr)); /* *---------------------------------------------------------------------- * * FileForRedirect -- * - * This procedure does much of the work of parsing redirection - * operators. It handles "@" if specified and allowed, and a file - * name, and opens the file if necessary. + * This function does much of the work of parsing redirection operators. + * It handles "@" if specified and allowed, and a file name, and opens + * the file if necessary. * * Results: - * The return value is the descriptor number for the file. If an - * error occurs then NULL is returned and an error message is left - * in the interp's result. Several arguments are side-effected; see - * the argument list below for details. + * The return value is the descriptor number for the file. If an error + * occurs then NULL is returned and an error message is left in the + * interp's result. Several arguments are side-effected; see the argument + * list below for details. * * Side effects: * None. @@ -67,22 +64,22 @@ static TclFile FileForRedirect(interp, spec, atOK, arg, nextArg, flags, skipPtr, closePtr, releasePtr) Tcl_Interp *interp; /* Intepreter to use for error reporting. */ - CONST char *spec; /* Points to character just after - * redirection character. */ - int atOK; /* Non-zero means that '@' notation can be + CONST char *spec; /* Points to character just after redirection + * character. */ + int atOK; /* Non-zero means that '@' notation can be * used to specify a channel, zero means that * it isn't. */ - CONST char *arg; /* Pointer to entire argument containing - * spec: used for error reporting. */ - CONST char *nextArg; /* Next argument in argc/argv array, if needed - * for file name or channel name. May be + CONST char *arg; /* Pointer to entire argument containing spec: + * used for error reporting. */ + CONST char *nextArg; /* Next argument in argc/argv array, if needed + * for file name or channel name. May be * NULL. */ - int flags; /* Flags to use for opening file or to - * specify mode for channel. */ - int *skipPtr; /* Filled with 1 if redirection target was - * in spec, 2 if it was in nextArg. */ - int *closePtr; /* Filled with one if the caller should - * close the file when done with it, zero + int flags; /* Flags to use for opening file or to specify + * mode for channel. */ + int *skipPtr; /* Filled with 1 if redirection target was in + * spec, 2 if it was in nextArg. */ + int *closePtr; /* Filled with one if the caller should close + * the file when done with it, zero * otherwise. */ int *releasePtr; { @@ -113,11 +110,9 @@ FileForRedirect(interp, spec, atOK, arg, nextArg, flags, skipPtr, closePtr, } *releasePtr = 1; if (writing) { - /* - * Be sure to flush output to the file, so that anything - * written by the child appears after stuff we've already - * written. + * Be sure to flush output to the file, so that anything written + * by the child appears after stuff we've already written. */ Tcl_Flush(chan); @@ -150,7 +145,7 @@ FileForRedirect(interp, spec, atOK, arg, nextArg, flags, skipPtr, closePtr, } return file; - badLastArg: + badLastArg: Tcl_AppendResult(interp, "can't specify \"", arg, "\" as last word in command", (char *) NULL); return NULL; @@ -161,10 +156,9 @@ FileForRedirect(interp, spec, atOK, arg, nextArg, flags, skipPtr, closePtr, * * Tcl_DetachPids -- * - * This procedure is called to indicate that one or more child - * processes have been placed in background and will never be - * waited for; they should eventually be reaped by - * Tcl_ReapDetachedProcs. + * This function is called to indicate that one or more child processes + * have been placed in background and will never be waited for; they + * should eventually be reaped by Tcl_ReapDetachedProcs. * * Results: * None. @@ -177,8 +171,8 @@ FileForRedirect(interp, spec, atOK, arg, nextArg, flags, skipPtr, closePtr, void Tcl_DetachPids(numPids, pidPtr) - int numPids; /* Number of pids to detach: gives size - * of array pointed to by pidPtr. */ + int numPids; /* Number of pids to detach: gives size of + * array pointed to by pidPtr. */ Tcl_Pid *pidPtr; /* Array of pids to detach. */ { register Detached *detPtr; @@ -200,17 +194,16 @@ Tcl_DetachPids(numPids, pidPtr) * * Tcl_ReapDetachedProcs -- * - * This procedure checks to see if any detached processes have - * exited and, if so, it "reaps" them by officially waiting on - * them. It should be called "occasionally" to make sure that - * all detached processes are eventually reaped. + * This function checks to see if any detached processes have exited and, + * if so, it "reaps" them by officially waiting on them. It should be + * called "occasionally" to make sure that all detached processes are + * eventually reaped. * * Results: * None. * * Side effects: - * Processes are waited on, so that they can be reaped by the - * system. + * Processes are waited on, so that they can be reaped by the system. * *---------------------------------------------------------------------- */ @@ -248,19 +241,19 @@ Tcl_ReapDetachedProcs() * * TclCleanupChildren -- * - * This is a utility procedure used to wait for child processes - * to exit, record information about abnormal exits, and then - * collect any stderr output generated by them. + * This is a utility function used to wait for child processes to exit, + * record information about abnormal exits, and then collect any stderr + * output generated by them. * * Results: - * The return value is a standard Tcl result. If anything at - * weird happened with the child processes, TCL_ERROR is returned - * and a message is left in the interp's result. + * The return value is a standard Tcl result. If anything at weird + * happened with the child processes, TCL_ERROR is returned and a message + * is left in the interp's result. * * Side effects: - * If the last character of the interp's result is a newline, then it - * is removed unless keepNewline is non-zero. File errorId gets - * closed, and pidPtr is freed back to the storage allocator. + * If the last character of the interp's result is a newline, then it is + * removed unless keepNewline is non-zero. File errorId gets closed, and + * pidPtr is freed back to the storage allocator. * *---------------------------------------------------------------------- */ @@ -271,7 +264,7 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) int numPids; /* Number of entries in pidPtr array. */ Tcl_Pid *pidPtr; /* Array of process ids of children. */ Tcl_Channel errorChan; /* Channel for file containing stderr output - * from pipeline. NULL means there isn't any + * from pipeline. NULL means there isn't any * stderr output. */ { int result = TCL_OK; @@ -284,11 +277,11 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) abnormalExit = 0; for (i = 0; i < numPids; i++) { /* - * We need to get the resolved pid before we wait on it as - * the windows implimentation of Tcl_WaitPid deletes the - * information such that any following calls to TclpGetPid - * fail. + * We need to get the resolved pid before we wait on it as the windows + * implimentation of Tcl_WaitPid deletes the information such that any + * following calls to TclpGetPid fail. */ + resolvedPid = TclpGetPid(pidPtr[i]); pid = Tcl_WaitPid(pidPtr[i], (int *) &waitStatus, 0); if (pid == (Tcl_Pid) -1) { @@ -297,9 +290,9 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) msg = Tcl_PosixError(interp); if (errno == ECHILD) { /* - * This changeup in message suggested by Mark Diekhans - * to remind people that ECHILD errors can occur on - * some systems if SIGCHLD isn't in its default state. + * This changeup in message suggested by Mark Diekhans to + * remind people that ECHILD errors can occur on some + * systems if SIGCHLD isn't in its default state. */ msg = @@ -312,10 +305,10 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) } /* - * Create error messages for unusual process exits. An - * extra newline gets appended to each error message, but - * it gets removed below (in the same fashion that an - * extra newline in the command's output is removed). + * Create error messages for unusual process exits. An extra newline + * gets appended to each error message, but it gets removed below (in + * the same fashion that an extra newline in the command's output is + * removed). */ if (!WIFEXITED(waitStatus) || (WEXITSTATUS(waitStatus) != 0)) { @@ -363,14 +356,12 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) } /* - * Read the standard error file. If there's anything there, - * then return an error and add the file's contents to the result - * string. + * Read the standard error file. If there's anything there, then return an + * error and add the file's contents to the result string. */ anyErrorInfo = 0; if (errorChan != NULL) { - /* * Make sure we start at the beginning of the file. */ @@ -400,8 +391,8 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) } /* - * If a child exited abnormally but didn't output any error information - * at all, generate an error message here. + * If a child exited abnormally but didn't output any error information at + * all, generate an error message here. */ if ((abnormalExit != 0) && (anyErrorInfo == 0) && (interp != NULL)) { @@ -416,25 +407,23 @@ TclCleanupChildren(interp, numPids, pidPtr, errorChan) * * TclCreatePipeline -- * - * Given an argc/argv array, instantiate a pipeline of processes - * as described by the argv. + * Given an argc/argv array, instantiate a pipeline of processes as + * described by the argv. * - * This procedure is unofficially exported for use by BLT. + * This function is unofficially exported for use by BLT. * * Results: - * The return value is a count of the number of new processes - * created, or -1 if an error occurred while creating the pipeline. - * *pidArrayPtr is filled in with the address of a dynamically - * allocated array giving the ids of all of the processes. It - * is up to the caller to free this array when it isn't needed - * anymore. If inPipePtr is non-NULL, *inPipePtr is filled in - * with the file id for the input pipe for the pipeline (if any): - * the caller must eventually close this file. If outPipePtr - * isn't NULL, then *outPipePtr is filled in with the file id - * for the output pipe from the pipeline: the caller must close - * this file. If errFilePtr isn't NULL, then *errFilePtr is filled - * with a file id that may be used to read error output after the - * pipeline completes. + * The return value is a count of the number of new processes created, or + * -1 if an error occurred while creating the pipeline. *pidArrayPtr is + * filled in with the address of a dynamically allocated array giving the + * ids of all of the processes. It is up to the caller to free this array + * when it isn't needed anymore. If inPipePtr is non-NULL, *inPipePtr is + * filled in with the file id for the input pipe for the pipeline (if + * any): the caller must eventually close this file. If outPipePtr isn't + * NULL, then *outPipePtr is filled in with the file id for the output + * pipe from the pipeline: the caller must close this file. If errFilePtr + * isn't NULL, then *errFilePtr is filled with a file id that may be used + * to read error output after the pipeline completes. * * Side effects: * Processes and pipes are created. @@ -448,62 +437,62 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, Tcl_Interp *interp; /* Interpreter to use for error reporting. */ int argc; /* Number of entries in argv. */ CONST char **argv; /* Array of strings describing commands in - * pipeline plus I/O redirection with <, - * <<, >, etc. Argv[argc] must be NULL. */ + * pipeline plus I/O redirection with <, <<, + * >, etc. Argv[argc] must be NULL. */ Tcl_Pid **pidArrayPtr; /* Word at *pidArrayPtr gets filled in with - * address of array of pids for processes - * in pipeline (first pid is first process - * in pipeline). */ + * address of array of pids for processes in + * pipeline (first pid is first process in + * pipeline). */ TclFile *inPipePtr; /* If non-NULL, input to the pipeline comes * from a pipe (unless overridden by - * redirection in the command). The file - * id with which to write to this pipe is - * stored at *inPipePtr. NULL means command - * specified its own input source. */ - TclFile *outPipePtr; /* If non-NULL, output to the pipeline goes - * to a pipe, unless overriden by redirection - * in the command. The file id with which to - * read frome this pipe is stored at - * *outPipePtr. NULL means command specified - * its own output sink. */ + * redirection in the command). The file id + * with which to write to this pipe is stored + * at *inPipePtr. NULL means command specified + * its own input source. */ + TclFile *outPipePtr; /* If non-NULL, output to the pipeline goes to + * a pipe, unless overriden by redirection in + * the command. The file id with which to read + * frome this pipe is stored at *outPipePtr. + * NULL means command specified its own output + * sink. */ TclFile *errFilePtr; /* If non-NULL, all stderr output from the * pipeline will go to a temporary file - * created here, and a descriptor to read - * the file will be left at *errFilePtr. - * The file will be removed already, so - * closing this descriptor will be the end - * of the file. If this is NULL, then - * all stderr output goes to our stderr. - * If the pipeline specifies redirection - * then the file will still be created - * but it will never get any data. */ + * created here, and a descriptor to read the + * file will be left at *errFilePtr. The file + * will be removed already, so closing this + * descriptor will be the end of the file. If + * this is NULL, then all stderr output goes + * to our stderr. If the pipeline specifies + * redirection then the file will still be + * created but it will never get any data. */ { - Tcl_Pid *pidPtr = NULL; /* Points to malloc-ed array holding all - * the pids of child processes. */ - int numPids; /* Actual number of processes that exist - * at *pidPtr right now. */ - int cmdCount; /* Count of number of distinct commands - * found in argc/argv. */ - CONST char *inputLiteral = NULL; /* If non-null, then this points to a - * string containing input data (specified - * via <<) to be piped to the first process - * in the pipeline. */ + Tcl_Pid *pidPtr = NULL; /* Points to malloc-ed array holding all the + * pids of child processes. */ + int numPids; /* Actual number of processes that exist at + * *pidPtr right now. */ + int cmdCount; /* Count of number of distinct commands found + * in argc/argv. */ + CONST char *inputLiteral = NULL; + /* If non-null, then this points to a string + * containing input data (specified via <<) to + * be piped to the first process in the + * pipeline. */ TclFile inputFile = NULL; /* If != NULL, gives file to use as input for * first process in pipeline (specified via < * or <@). */ - int inputClose = 0; /* If non-zero, then inputFile should be + int inputClose = 0; /* If non-zero, then inputFile should be * closed when cleaning up. */ int inputRelease = 0; TclFile outputFile = NULL; /* Writable file for output from last command - * in pipeline (could be file or pipe). NULL + * in pipeline (could be file or pipe). NULL * means use stdout. */ - int outputClose = 0; /* If non-zero, then outputFile should be + int outputClose = 0; /* If non-zero, then outputFile should be * closed when cleaning up. */ int outputRelease = 0; TclFile errorFile = NULL; /* Writable file for error output from all - * commands in pipeline. NULL means use + * commands in pipeline. NULL means use * stderr. */ - int errorClose = 0; /* If non-zero, then errorFile should be + int errorClose = 0; /* If non-zero, then errorFile should be * closed when cleaning up. */ int errorRelease = 0; CONST char *p; @@ -531,16 +520,16 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, numPids = 0; /* - * First, scan through all the arguments to figure out the structure - * of the pipeline. Process all of the input and output redirection - * arguments and remove them from the argument list in the pipeline. - * Count the number of distinct processes (it's the number of "|" - * arguments plus one) but don't remove the "|" arguments because - * they'll be used in the second pass to seperate the individual - * child processes. Cannot start the child processes in this pass - * because the redirection symbols may appear anywhere in the - * command line -- e.g., the '<' that specifies the input to the - * entire pipe may appear at the very end of the argument list. + * First, scan through all the arguments to figure out the structure of + * the pipeline. Process all of the input and output redirection arguments + * and remove them from the argument list in the pipeline. Count the + * number of distinct processes (it's the number of "|" arguments plus + * one) but don't remove the "|" arguments because they'll be used in the + * second pass to seperate the individual child processes. Cannot start + * the child processes in this pass because the redirection symbols may + * appear anywhere in the command line - e.g., the '<' that specifies the + * input to the entire pipe may appear at the very end of the argument + * list. */ lastBar = -1; @@ -556,8 +545,7 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, } if (*p == '\0') { if ((i == (lastBar + 1)) || (i == (argc - 1))) { - Tcl_SetResult(interp, - "illegal use of | or |& in command", + Tcl_SetResult(interp, "illegal use of | or |& in command", TCL_STATIC); goto error; } @@ -590,8 +578,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, } } else { inputLiteral = NULL; - inputFile = FileForRedirect(interp, p, 1, argv[i], - argv[i + 1], O_RDONLY, &skip, &inputClose, &inputRelease); + inputFile = FileForRedirect(interp, p, 1, argv[i], argv[i+1], + O_RDONLY, &skip, &inputClose, &inputRelease); if (inputFile == NULL) { goto error; } @@ -616,8 +604,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, } /* - * Close the old output file, but only if the error file is - * not also using it. + * Close the old output file, but only if the error file is not + * also using it. */ if (outputClose != 0) { @@ -636,8 +624,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, TclpReleaseFile(outputFile); } } - outputFile = FileForRedirect(interp, p, atOK, argv[i], - argv[i + 1], flags, &skip, &outputClose, &outputRelease); + outputFile = FileForRedirect(interp, p, atOK, argv[i], argv[i+1], + flags, &skip, &outputClose, &outputRelease); if (outputFile == NULL) { goto error; } @@ -677,10 +665,11 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, if (atOK && p[0] == '@' && p[1] == '1' && p[2] == '\0') { /* * Special case handling of 2>@1 to redirect stderr to the - * exec/open output pipe as well. This is meant for the end - * of the command string, otherwise use |& between commands. + * exec/open output pipe as well. This is meant for the end of + * the command string, otherwise use |& between commands. */ - if (i != argc - 1) { + + if (i != argc-1) { Tcl_AppendResult(interp, "must specify \"", argv[i], "\" as last word in command", (char *) NULL); goto error; @@ -690,7 +679,7 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, skip = 1; } else { errorFile = FileForRedirect(interp, p, atOK, argv[i], - argv[i + 1], flags, &skip, &errorClose, &errorRelease); + argv[i+1], flags, &skip, &errorClose, &errorRelease); if (errorFile == NULL) { goto error; } @@ -711,9 +700,10 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, if (inputLiteral != NULL) { /* * The input for the first process is immediate data coming from - * Tcl. Create a temporary file for it and put the data into the + * Tcl. Create a temporary file for it and put the data into the * file. */ + inputFile = TclpCreateTempFile(inputLiteral); if (inputFile == NULL) { Tcl_AppendResult(interp, @@ -724,8 +714,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, inputClose = 1; } else if (inPipePtr != NULL) { /* - * The input for the first process in the pipeline is to - * come from a pipe that can be written from by the caller. + * The input for the first process in the pipeline is to come from + * a pipe that can be written from by the caller. */ if (TclpCreatePipe(&inputFile, inPipePtr) == 0) { @@ -753,8 +743,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, if (outputFile == NULL) { if (outPipePtr != NULL) { /* - * Output from the last process in the pipeline is to go to a - * pipe that can be read by the caller. + * Output from the last process in the pipeline is to go to a pipe + * that can be read by the caller. */ if (TclpCreatePipe(outPipePtr, &outputFile) == 0) { @@ -782,16 +772,17 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, if (errorFile == NULL) { if (errorToOutput == 2) { /* - * Handle 2>@1 special case at end of cmd line + * Handle 2>@1 special case at end of cmd line. */ + errorFile = outputFile; } else if (errFilePtr != NULL) { /* * Set up the standard error output sink for the pipeline, if - * requested. Use a temporary file which is opened, then deleted. + * requested. Use a temporary file which is opened, then deleted. * Could potentially just use pipe, but if it filled up it could - * cause the pipeline to deadlock: we'd be waiting for processes - * to complete before reading stderr, and processes couldn't + * cause the pipeline to deadlock: we'd be waiting for processes + * to complete before reading stderr, and processes couldn't * complete because stderr was backed up. */ @@ -819,8 +810,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, } /* - * Scan through the argc array, creating a process for each - * group of arguments between the "|" characters. + * Scan through the argc array, creating a process for each group of + * arguments between the "|" characters. */ Tcl_ReapDetachedProcs(); @@ -861,7 +852,7 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, /* * If this is the last segment, use the specified outputFile. - * Otherwise create an intermediate pipe. pipeIn will become the + * Otherwise create an intermediate pipe. pipeIn will become the * curInFile for the next segment of the pipe. */ @@ -900,8 +891,8 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, numPids++; /* - * Close off our copies of file descriptors that were set up for - * this child, then set up the input for the next child. + * Close off our copies of file descriptors that were set up for this + * child, then set up the input for the next child. */ if ((curInFile != NULL) && (curInFile != inputFile)) { @@ -919,10 +910,10 @@ TclCreatePipeline(interp, argc, argv, pidArrayPtr, inPipePtr, *pidArrayPtr = pidPtr; /* - * All done. Cleanup open files lying around and then return. + * All done. Cleanup open files lying around and then return. */ -cleanup: + cleanup: Tcl_DStringFree(&execBuffer); if (inputClose) { @@ -943,12 +934,12 @@ cleanup: return numPids; /* - * An error occurred. There could have been extra files open, such - * as pipes between children. Clean them all up. Detach any child - * processes that have been created. + * An error occurred. There could have been extra files open, such as + * pipes between children. Clean them all up. Detach any child processes + * that have been created. */ -error: + error: if (pipeIn != NULL) { TclpCloseFile(pipeIn); } @@ -987,28 +978,26 @@ error: * * Tcl_OpenCommandChannel -- * - * Opens an I/O channel to one or more subprocesses specified - * by argc and argv. The flags argument determines the - * disposition of the stdio handles. If the TCL_STDIN flag is - * set then the standard input for the first subprocess will - * be tied to the channel: writing to the channel will provide - * input to the subprocess. If TCL_STDIN is not set, then - * standard input for the first subprocess will be the same as - * this application's standard input. If TCL_STDOUT is set then - * standard output from the last subprocess can be read from the - * channel; otherwise it goes to this application's standard - * output. If TCL_STDERR is set, standard error output for all - * subprocesses is returned to the channel and results in an error - * when the channel is closed; otherwise it goes to this - * application's standard error. If TCL_ENFORCE_MODE is not set, - * then argc and argv can redirect the stdio handles to override - * TCL_STDIN, TCL_STDOUT, and TCL_STDERR; if it is set, then it - * is an error for argc and argv to override stdio channels for - * which TCL_STDIN, TCL_STDOUT, and TCL_STDERR have been set. + * Opens an I/O channel to one or more subprocesses specified by argc and + * argv. The flags argument determines the disposition of the stdio + * handles. If the TCL_STDIN flag is set then the standard input for the + * first subprocess will be tied to the channel: writing to the channel + * will provide input to the subprocess. If TCL_STDIN is not set, then + * standard input for the first subprocess will be the same as this + * application's standard input. If TCL_STDOUT is set then standard + * output from the last subprocess can be read from the channel; + * otherwise it goes to this application's standard output. If TCL_STDERR + * is set, standard error output for all subprocesses is returned to the + * channel and results in an error when the channel is closed; otherwise + * it goes to this application's standard error. If TCL_ENFORCE_MODE is + * not set, then argc and argv can redirect the stdio handles to override + * TCL_STDIN, TCL_STDOUT, and TCL_STDERR; if it is set, then it is an + * error for argc and argv to override stdio channels for which + * TCL_STDIN, TCL_STDOUT, and TCL_STDERR have been set. * * Results: - * A new command channel, or NULL on failure with an error - * message left in interp. + * A new command channel, or NULL on failure with an error message left + * in interp. * * Side effects: * Creates processes, opens pipes. @@ -1018,8 +1007,8 @@ error: Tcl_Channel Tcl_OpenCommandChannel(interp, argc, argv, flags) - Tcl_Interp *interp; /* Interpreter for error reporting. Can - * NOT be NULL. */ + Tcl_Interp *interp; /* Interpreter for error reporting. Can NOT be + * NULL. */ int argc; /* How many arguments. */ CONST char **argv; /* Array of arguments for command pipe. */ int flags; /* Or'ed combination of TCL_STDIN, TCL_STDOUT, @@ -1045,8 +1034,8 @@ Tcl_OpenCommandChannel(interp, argc, argv, flags) } /* - * Verify that the pipes that were created satisfy the - * readable/writable constraints. + * Verify that the pipes that were created satisfy the readable/writable + * constraints. */ if (flags & TCL_ENFORCE_MODE) { @@ -1072,7 +1061,7 @@ Tcl_OpenCommandChannel(interp, argc, argv, flags) } return channel; -error: + error: if (numPids > 0) { Tcl_DetachPids(numPids, pidPtr); ckfree((char *) pidPtr); @@ -1088,3 +1077,11 @@ error: } return NULL; } + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |