commit 78e54359372d02d17e9ab453c7bc0cd725b807f2
parent f0ca847fca5100dd98fbbed9c49b08ba5f310ac5
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date: Thu, 5 May 2022 06:28:11 +0200
sfeed_curses: close stdin for spawning a plumb program in non-interactive mode
This is only for plumbing in non-interactive mode in forkexec(), but not piping
content.
Probably obvious what the descriptors are, but also add a few comments to dup2
of the file descriptors (stdin, stdout, stderr).
To reproduce a behaviour:
Plumb script:
#!/bin/sh
dmenu
Then launch it:
SFEED_PLUMB_INTERACTIVE=0 SFEED_PLUMB=thescript sfeed_curses ~/.sfeed/feeds/*
The program now waits on input while in non-interactive mode and only seems to
hang.
After:
The program starts but just has no input passed to it.
Diffstat:
2 files changed, 9 insertions(+), 7 deletions(-)
diff --git a/sfeed_curses.1 b/sfeed_curses.1
@@ -1,4 +1,4 @@
-.Dd May 4, 2022
+.Dd May 5, 2022
.Dt SFEED_CURSES 1
.Os
.Sh NAME
@@ -290,6 +290,7 @@ In non-interactive mode
.Nm
doesn't wait until the process exits.
Stdout and stderr of the program are not written as output.
+When plumbing an URL then stdin is closed also.
.Sh EXIT STATUS
.Ex -std
The exit status is 130 on SIGINT and 143 on SIGTERM.
diff --git a/sfeed_curses.c b/sfeed_curses.c
@@ -604,8 +604,8 @@ pipeitem(const char *cmd, struct item *item, int field, int interactive)
die("fork");
case 0:
if (!interactive) {
- dup2(devnullfd, 1);
- dup2(devnullfd, 2);
+ dup2(devnullfd, 1); /* stdout */
+ dup2(devnullfd, 2); /* stderr */
}
errno = 0;
@@ -642,8 +642,9 @@ forkexec(char *argv[], int interactive)
die("fork");
case 0:
if (!interactive) {
- dup2(devnullfd, 1);
- dup2(devnullfd, 2);
+ dup2(devnullfd, 0); /* stdin */
+ dup2(devnullfd, 1); /* stdout */
+ dup2(devnullfd, 2); /* stderr */
}
if (execvp(argv[0], argv) == -1)
_exit(1);
@@ -1847,8 +1848,8 @@ markread(struct pane *p, off_t from, off_t to, int isread)
case -1:
die("fork");
case 0:
- dup2(devnullfd, 1);
- dup2(devnullfd, 2);
+ dup2(devnullfd, 1); /* stdout */
+ dup2(devnullfd, 2); /* stderr */
errno = 0;
if (!(fp = popen(cmd, "w")))
