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diff --git a/man2/execve.2 b/man2/execve.2 deleted file mode 100644 index 23404b5..0000000 --- a/man2/execve.2 +++ /dev/null @@ -1,889 +0,0 @@ -.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992 -.\" and Copyright (c) 2006 Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt <michael@moria.de> -.\" Modified 1993-07-21 by Rik Faith <faith@cs.unc.edu> -.\" Modified 1994-08-21 by Michael Chastain <mec@shell.portal.com>: -.\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com> -.\" Modified 1999-11-12 by Urs Thuermann <urs@isnogud.escape.de> -.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" 2006-09-04 Michael Kerrisk <mtk.manpages@gmail.com> -.\" Added list of process attributes that are not preserved on exec(). -.\" 2007-09-14 Ollie Wild <aaw@google.com>, mtk -.\" Add text describing limits on command-line arguments + environment -.\" -.TH execve 2 2023-11-01 "Linux man-pages 6.7" -.SH NAME -execve \- execute program -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.BI "int execve(const char *" pathname ", char *const _Nullable " argv [], -.BI " char *const _Nullable " envp []); -.fi -.SH DESCRIPTION -.BR execve () -executes the program referred to by \fIpathname\fP. -This causes the program that is currently being run by the calling process -to be replaced with a new program, with newly initialized stack, heap, -and (initialized and uninitialized) data segments. -.P -\fIpathname\fP must be either a binary executable, or a script -starting with a line of the form: -.P -.in +4n -.EX -\fB#!\fP\fIinterpreter \fP[optional-arg] -.EE -.in -.P -For details of the latter case, see "Interpreter scripts" below. -.P -.I argv -is an array of pointers to strings passed to the new program -as its command-line arguments. -By convention, the first of these strings (i.e., -.IR argv[0] ) -should contain the filename associated with the file being executed. -The -.I argv -array must be terminated by a null pointer. -(Thus, in the new program, -.I argv[argc] -will be a null pointer.) -.P -.I envp -is an array of pointers to strings, conventionally of the form -.BR key=value , -which are passed as the environment of the new program. -The -.I envp -array must be terminated by a null pointer. -.P -This manual page describes the Linux system call in detail; -for an overview of the nomenclature and the many, often preferable, -standardised variants of this function provided by libc, -including ones that search the -.B PATH -environment variable, see -.BR exec (3). -.P -The argument vector and environment can be accessed by the -new program's main function, when it is defined as: -.P -.in +4n -.EX -int main(int argc, char *argv[], char *envp[]) -.EE -.in -.P -Note, however, that the use of a third argument to the main function -is not specified in POSIX.1; -according to POSIX.1, -the environment should be accessed via the external variable -.BR environ (7). -.P -.BR execve () -does not return on success, and the text, initialized data, -uninitialized data (bss), and stack of the calling process are overwritten -according to the contents of the newly loaded program. -.P -If the current program is being ptraced, a \fBSIGTRAP\fP signal is sent to it -after a successful -.BR execve (). -.P -If the set-user-ID bit is set on the program file referred to by -\fIpathname\fP, -then the effective user ID of the calling process is changed -to that of the owner of the program file. -Similarly, if the set-group-ID bit is set on the program file, -then the effective group ID of the calling -process is set to the group of the program file. -.P -The aforementioned transformations of the effective IDs are -.I not -performed (i.e., the set-user-ID and set-group-ID bits are ignored) -if any of the following is true: -.IP \[bu] 3 -the -.I no_new_privs -attribute is set for the calling thread (see -.BR prctl (2)); -.IP \[bu] -the underlying filesystem is mounted -.I nosuid -(the -.B MS_NOSUID -flag for -.BR mount (2)); -or -.IP \[bu] -the calling process is being ptraced. -.P -The capabilities of the program file (see -.BR capabilities (7)) -are also ignored if any of the above are true. -.P -The effective user ID of the process is copied to the saved set-user-ID; -similarly, the effective group ID is copied to the saved set-group-ID. -This copying takes place after any effective ID changes that occur -because of the set-user-ID and set-group-ID mode bits. -.P -The process's real UID and real GID, as well as its supplementary group IDs, -are unchanged by a call to -.BR execve (). -.P -If the executable is an a.out dynamically linked -binary executable containing -shared-library stubs, the Linux dynamic linker -.BR ld.so (8) -is called at the start of execution to bring -needed shared objects into memory -and link the executable with them. -.P -If the executable is a dynamically linked ELF executable, the -interpreter named in the PT_INTERP segment is used to load the needed -shared objects. -This interpreter is typically -.I /lib/ld\-linux.so.2 -for binaries linked with glibc (see -.BR ld\-linux.so (8)). -.\" -.SS Effect on process attributes -All process attributes are preserved during an -.BR execve (), -except the following: -.IP \[bu] 3 -The dispositions of any signals that are being caught are -reset to the default -.RB ( signal (7)). -.IP \[bu] -Any alternate signal stack is not preserved -.RB ( sigaltstack (2)). -.IP \[bu] -Memory mappings are not preserved -.RB ( mmap (2)). -.IP \[bu] -Attached System\ V shared memory segments are detached -.RB ( shmat (2)). -.IP \[bu] -POSIX shared memory regions are unmapped -.RB ( shm_open (3)). -.IP \[bu] -Open POSIX message queue descriptors are closed -.RB ( mq_overview (7)). -.IP \[bu] -Any open POSIX named semaphores are closed -.RB ( sem_overview (7)). -.IP \[bu] -POSIX timers are not preserved -.RB ( timer_create (2)). -.IP \[bu] -Any open directory streams are closed -.RB ( opendir (3)). -.IP \[bu] -Memory locks are not preserved -.RB ( mlock (2), -.BR mlockall (2)). -.IP \[bu] -Exit handlers are not preserved -.RB ( atexit (3), -.BR on_exit (3)). -.IP \[bu] -The floating-point environment is reset to the default (see -.BR fenv (3)). -.P -The process attributes in the preceding list are all specified -in POSIX.1. -The following Linux-specific process attributes are also -not preserved during an -.BR execve (): -.IP \[bu] 3 -The process's "dumpable" attribute is set to the value 1, -unless a set-user-ID program, a set-group-ID program, -or a program with capabilities is being executed, -in which case the dumpable flag may instead be reset to the value in -.IR /proc/sys/fs/suid_dumpable , -in the circumstances described under -.B PR_SET_DUMPABLE -in -.BR prctl (2). -Note that changes to the "dumpable" attribute may cause ownership -of files in the process's -.IR /proc/ pid -directory to change to -.IR root:root , -as described in -.BR proc (5). -.IP \[bu] -The -.BR prctl (2) -.B PR_SET_KEEPCAPS -flag is cleared. -.IP \[bu] -(Since Linux 2.4.36 / 2.6.23) -If a set-user-ID or set-group-ID program is being executed, -then the parent death signal set by -.BR prctl (2) -.B PR_SET_PDEATHSIG -flag is cleared. -.IP \[bu] -The process name, as set by -.BR prctl (2) -.B PR_SET_NAME -(and displayed by -.IR "ps\ \-o comm" ), -is reset to the name of the new executable file. -.IP \[bu] -The -.B SECBIT_KEEP_CAPS -.I securebits -flag is cleared. -See -.BR capabilities (7). -.IP \[bu] -The termination signal is reset to -.B SIGCHLD -(see -.BR clone (2)). -.IP \[bu] -The file descriptor table is unshared, undoing the effect of the -.B CLONE_FILES -flag of -.BR clone (2). -.P -Note the following further points: -.IP \[bu] 3 -All threads other than the calling thread are destroyed during an -.BR execve (). -Mutexes, condition variables, and other pthreads objects are not preserved. -.IP \[bu] -The equivalent of \fIsetlocale(LC_ALL, "C")\fP -is executed at program start-up. -.IP \[bu] -POSIX.1 specifies that the dispositions of any signals that -are ignored or set to the default are left unchanged. -POSIX.1 specifies one exception: if -.B SIGCHLD -is being ignored, -then an implementation may leave the disposition unchanged or -reset it to the default; Linux does the former. -.IP \[bu] -Any outstanding asynchronous I/O operations are canceled -.RB ( aio_read (3), -.BR aio_write (3)). -.IP \[bu] -For the handling of capabilities during -.BR execve (), -see -.BR capabilities (7). -.IP \[bu] -By default, file descriptors remain open across an -.BR execve (). -File descriptors that are marked close-on-exec are closed; -see the description of -.B FD_CLOEXEC -in -.BR fcntl (2). -(If a file descriptor is closed, this will cause the release -of all record locks obtained on the underlying file by this process. -See -.BR fcntl (2) -for details.) -POSIX.1 says that if file descriptors 0, 1, and 2 would -otherwise be closed after a successful -.BR execve (), -and the process would gain privilege because the set-user-ID or -set-group-ID mode bit was set on the executed file, -then the system may open an unspecified file for each of these -file descriptors. -As a general principle, no portable program, whether privileged or not, -can assume that these three file descriptors will remain -closed across an -.BR execve (). -.\" On Linux it appears that these file descriptors are -.\" always open after an execve(), and it looks like -.\" Solaris 8 and FreeBSD 6.1 are the same. -- mtk, 30 Apr 2007 -.SS Interpreter scripts -An interpreter script is a text file that has execute -permission enabled and whose first line is of the form: -.P -.in +4n -.EX -\fB#!\fP\fIinterpreter \fP[optional-arg] -.EE -.in -.P -The -.I interpreter -must be a valid pathname for an executable file. -.P -If the -.I pathname -argument of -.BR execve () -specifies an interpreter script, then -.I interpreter -will be invoked with the following arguments: -.P -.in +4n -.EX -\fIinterpreter\fP [optional-arg] \fIpathname\fP arg... -.EE -.in -.P -where -.I pathname -is the pathname of the file specified as the first argument of -.BR execve (), -and -.I arg... -is the series of words pointed to by the -.I argv -argument of -.BR execve (), -starting at -.IR argv[1] . -Note that there is no way to get the -.I argv[0] -that was passed to the -.BR execve () -call. -.\" See the P - preserve-argv[0] option. -.\" Documentation/admin-guide/binfmt-misc.rst -.\" https://www.kernel.org/doc/html/latest/admin-guide/binfmt-misc.html -.P -For portable use, -.I optional-arg -should either be absent, or be specified as a single word (i.e., it -should not contain white space); see NOTES below. -.P -Since Linux 2.6.28, -.\" commit bf2a9a39639b8b51377905397a5005f444e9a892 -the kernel permits the interpreter of a script to itself be a script. -This permission is recursive, up to a limit of four recursions, -so that the interpreter may be a script which is interpreted by a script, -and so on. -.SS Limits on size of arguments and environment -Most UNIX implementations impose some limit on the total size -of the command-line argument -.RI ( argv ) -and environment -.RI ( envp ) -strings that may be passed to a new program. -POSIX.1 allows an implementation to advertise this limit using the -.B ARG_MAX -constant (either defined in -.I <limits.h> -or available at run time using the call -.IR "sysconf(_SC_ARG_MAX)" ). -.P -Before Linux 2.6.23, the memory used to store the -environment and argument strings was limited to 32 pages -(defined by the kernel constant -.BR MAX_ARG_PAGES ). -On architectures with a 4-kB page size, -this yields a maximum size of 128\ kB. -.P -On Linux 2.6.23 and later, most architectures support a size limit -derived from the soft -.B RLIMIT_STACK -resource limit (see -.BR getrlimit (2)) -that is in force at the time of the -.BR execve () -call. -(Architectures with no memory management unit are excepted: -they maintain the limit that was in effect before Linux 2.6.23.) -This change allows programs to have a much larger -argument and/or environment list. -.\" For some background on the changes to ARG_MAX in Linux 2.6.23 and -.\" Linux 2.6.25, see: -.\" http://sourceware.org/bugzilla/show_bug.cgi?id=5786 -.\" http://bugzilla.kernel.org/show_bug.cgi?id=10095 -.\" http://thread.gmane.org/gmane.linux.kernel/646709/focus=648101, -.\" checked into Linux 2.6.25 as commit a64e715fc74b1a7dcc5944f848acc38b2c4d4ee2. -For these architectures, the total size is limited to 1/4 of the allowed -stack size. -(Imposing the 1/4-limit -ensures that the new program always has some stack space.) -.\" Ollie: That doesn't include the lists of pointers, though, -.\" so the actual usage is a bit higher (1 pointer per argument). -Additionally, the total size is limited to 3/4 of the value -of the kernel constant -.B _STK_LIM -(8 MiB). -Since Linux 2.6.25, -the kernel also places a floor of 32 pages on this size limit, -so that, even when -.B RLIMIT_STACK -is set very low, -applications are guaranteed to have at least as much argument and -environment space as was provided by Linux 2.6.22 and earlier. -(This guarantee was not provided in Linux 2.6.23 and 2.6.24.) -Additionally, the limit per string is 32 pages (the kernel constant -.BR MAX_ARG_STRLEN ), -and the maximum number of strings is 0x7FFFFFFF. -.SH RETURN VALUE -On success, -.BR execve () -does not return, on error \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -.TP -.B E2BIG -The total number of bytes in the environment -.RI ( envp ) -and argument list -.RI ( argv ) -is too large, -an argument or environment string is too long, -or the full -.I pathname -of the executable is too long. -The terminating null byte is counted as part of the string length. -.TP -.B EACCES -Search permission is denied on a component of the path prefix of -.I pathname -or the name of a script interpreter. -(See also -.BR path_resolution (7).) -.TP -.B EACCES -The file or a script interpreter is not a regular file. -.TP -.B EACCES -Execute permission is denied for the file or a script or ELF interpreter. -.TP -.B EACCES -The filesystem is mounted -.IR noexec . -.TP -.BR EAGAIN " (since Linux 3.1)" -.\" commit 72fa59970f8698023045ab0713d66f3f4f96945c -Having changed its real UID using one of the -.BR set*uid () -calls, the caller was\[em]and is now still\[em]above its -.B RLIMIT_NPROC -resource limit (see -.BR setrlimit (2)). -For a more detailed explanation of this error, see NOTES. -.TP -.B EFAULT -.I pathname -or one of the pointers in the vectors -.I argv -or -.I envp -points outside your accessible address space. -.TP -.B EINVAL -An ELF executable had more than one PT_INTERP segment (i.e., tried to -name more than one interpreter). -.TP -.B EIO -An I/O error occurred. -.TP -.B EISDIR -An ELF interpreter was a directory. -.TP -.B ELIBBAD -An ELF interpreter was not in a recognized format. -.TP -.B ELOOP -Too many symbolic links were encountered in resolving -.I pathname -or the name of a script or ELF interpreter. -.TP -.B ELOOP -The maximum recursion limit was reached during recursive script -interpretation (see "Interpreter scripts", above). -Before Linux 3.8, -.\" commit d740269867021faf4ce38a449353d2b986c34a67 -the error produced for this case was -.BR ENOEXEC . -.TP -.B EMFILE -The per-process limit on the number of open file descriptors has been reached. -.TP -.B ENAMETOOLONG -.I pathname -is too long. -.TP -.B ENFILE -The system-wide limit on the total number of open files has been reached. -.TP -.B ENOENT -The file -.I pathname -or a script or ELF interpreter does not exist. -.TP -.B ENOEXEC -An executable is not in a recognized format, is for the wrong -architecture, or has some other format error that means it cannot be -executed. -.TP -.B ENOMEM -Insufficient kernel memory was available. -.TP -.B ENOTDIR -A component of the path prefix of -.I pathname -or a script or ELF interpreter is not a directory. -.TP -.B EPERM -The filesystem is mounted -.IR nosuid , -the user is not the superuser, -and the file has the set-user-ID or set-group-ID bit set. -.TP -.B EPERM -The process is being traced, the user is not the superuser and the -file has the set-user-ID or set-group-ID bit set. -.TP -.B EPERM -A "capability-dumb" applications would not obtain the full set of -permitted capabilities granted by the executable file. -See -.BR capabilities (7). -.TP -.B ETXTBSY -The specified executable was open for writing by one or more processes. -.SH VERSIONS -POSIX does not document the #! behavior, but it exists -(with some variations) on other UNIX systems. -.P -On Linux, -.I argv -and -.I envp -can be specified as NULL. -In both cases, this has the same effect as specifying the argument -as a pointer to a list containing a single null pointer. -.B "Do not take advantage of this nonstandard and nonportable misfeature!" -On many other UNIX systems, specifying -.I argv -as NULL will result in an error -.RB ( EFAULT ). -.I Some -other UNIX systems treat the -.I envp==NULL -case the same as Linux. -.\" e.g., EFAULT on Solaris 8 and FreeBSD 6.1; but -.\" HP-UX 11 is like Linux -- mtk, Apr 2007 -.\" Bug filed 30 Apr 2007: http://bugzilla.kernel.org/show_bug.cgi?id=8408 -.\" Bug rejected (because fix would constitute an ABI change). -.\" -.P -POSIX.1 says that values returned by -.BR sysconf (3) -should be invariant over the lifetime of a process. -However, since Linux 2.6.23, if the -.B RLIMIT_STACK -resource limit changes, then the value reported by -.B _SC_ARG_MAX -will also change, -to reflect the fact that the limit on space for holding -command-line arguments and environment variables has changed. -.\" -.SS Interpreter scripts -The kernel imposes a maximum length on the text that follows the -"#!" characters at the start of a script; -characters beyond the limit are ignored. -Before Linux 5.1, the limit is 127 characters. -Since Linux 5.1, -.\" commit 6eb3c3d0a52dca337e327ae8868ca1f44a712e02 -the limit is 255 characters. -.P -The semantics of the -.I optional-arg -argument of an interpreter script vary across implementations. -On Linux, the entire string following the -.I interpreter -name is passed as a single argument to the interpreter, -and this string can include white space. -However, behavior differs on some other systems. -Some systems -.\" e.g., Solaris 8 -use the first white space to terminate -.IR optional-arg . -On some systems, -.\" e.g., FreeBSD before 6.0, but not FreeBSD 6.0 onward -an interpreter script can have multiple arguments, -and white spaces in -.I optional-arg -are used to delimit the arguments. -.P -Linux (like most other modern UNIX systems) -ignores the set-user-ID and set-group-ID bits on scripts. -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, SVr4, 4.3BSD. -.\" SVr4 documents additional error -.\" conditions EAGAIN, EINTR, ELIBACC, ENOLINK, EMULTIHOP; POSIX does not -.\" document ETXTBSY, EPERM, EFAULT, ELOOP, EIO, ENFILE, EMFILE, EINVAL, -.\" EISDIR or ELIBBAD error conditions. -.P -With UNIX\ V6, the argument list of an -.BR exec () -call was ended by 0, -while the argument list of -.I main -was ended by \-1. -Thus, this argument list was not directly usable in a further -.BR exec () -call. -Since UNIX\ V7, both are NULL. -.SH NOTES -One sometimes sees -.BR execve () -(and the related functions described in -.BR exec (3)) -described as "executing a -.I new -process" (or similar). -This is a highly misleading description: -there is no new process; -many attributes of the calling process remain unchanged -(in particular, its PID). -All that -.BR execve () -does is arrange for an existing process (the calling process) -to execute a new program. -.P -Set-user-ID and set-group-ID processes can not be -.BR ptrace (2)d. -.P -The result of mounting a filesystem -.I nosuid -varies across Linux kernel versions: -some will refuse execution of set-user-ID and set-group-ID -executables when this would -give the user powers they did not have already (and return -.BR EPERM ), -some will just ignore the set-user-ID and set-group-ID bits and -.BR exec () -successfully. -.P -In most cases where -.BR execve () -fails, control returns to the original executable image, -and the caller of -.BR execve () -can then handle the error. -However, in (rare) cases (typically caused by resource exhaustion), -failure may occur past the point of no return: -the original executable image has been torn down, -but the new image could not be completely built. -In such cases, the kernel kills the process with a -.\" commit 19d860a140beac48a1377f179e693abe86a9dac9 -.B SIGSEGV -.RB ( SIGKILL -until Linux 3.17) -signal. -.SS execve() and EAGAIN -A more detailed explanation of the -.B EAGAIN -error that can occur (since Linux 3.1) when calling -.BR execve () -is as follows. -.P -The -.B EAGAIN -error can occur when a -.I preceding -call to -.BR setuid (2), -.BR setreuid (2), -or -.BR setresuid (2) -caused the real user ID of the process to change, -and that change caused the process to exceed its -.B RLIMIT_NPROC -resource limit (i.e., the number of processes belonging -to the new real UID exceeds the resource limit). -From Linux 2.6.0 to Linux 3.0, this caused the -.BR set*uid () -call to fail. -(Before Linux 2.6, -.\" commit 909cc4ae86f3380152a18e2a3c44523893ee11c4 -the resource limit was not imposed on processes that -changed their user IDs.) -.P -Since Linux 3.1, the scenario just described no longer causes the -.BR set*uid () -call to fail, -because it too often led to security holes where buggy applications -didn't check the return status and assumed -that\[em]if the caller had root privileges\[em]the call would always succeed. -Instead, the -.BR set*uid () -calls now successfully change the real UID, -but the kernel sets an internal flag, named -.BR PF_NPROC_EXCEEDED , -to note that the -.B RLIMIT_NPROC -resource limit has been exceeded. -If the -.B PF_NPROC_EXCEEDED -flag is set and the resource limit is still -exceeded at the time of a subsequent -.BR execve () -call, that call fails with the error -.BR EAGAIN . -This kernel logic ensures that the -.B RLIMIT_NPROC -resource limit is still enforced for the -common privileged daemon workflow\[em]namely, -.BR fork (2) -+ -.BR set*uid () -+ -.BR execve (). -.P -If the resource limit was not still exceeded at the time of the -.BR execve () -call -(because other processes belonging to this real UID terminated between the -.BR set*uid () -call and the -.BR execve () -call), then the -.BR execve () -call succeeds and the kernel clears the -.B PF_NPROC_EXCEEDED -process flag. -The flag is also cleared if a subsequent call to -.BR fork (2) -by this process succeeds. -.\" -.\" .SH BUGS -.\" Some Linux versions have failed to check permissions on ELF -.\" interpreters. This is a security hole, because it allows users to -.\" open any file, such as a rewinding tape device, for reading. Some -.\" Linux versions have also had other security holes in -.\" .BR execve () -.\" that could be exploited for denial of service by a suitably crafted -.\" ELF binary. There are no known problems with Linux 2.0.34 or Linux 2.2.15. -.SH EXAMPLES -The following program is designed to be execed by the second program below. -It just echoes its command-line arguments, one per line. -.P -.in +4n -.\" SRC BEGIN (myecho.c) -.EX -/* myecho.c */ -\& -#include <stdio.h> -#include <stdlib.h> -\& -int -main(int argc, char *argv[]) -{ - for (size_t j = 0; j < argc; j++) - printf("argv[%zu]: %s\en", j, argv[j]); -\& - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.in -.P -This program can be used to exec the program named in its command-line -argument: -.P -.in +4n -.\" SRC BEGIN (execve.c) -.EX -/* execve.c */ -\& -#include <stdio.h> -#include <stdlib.h> -#include <unistd.h> -\& -int -main(int argc, char *argv[]) -{ - static char *newargv[] = { NULL, "hello", "world", NULL }; - static char *newenviron[] = { NULL }; -\& - if (argc != 2) { - fprintf(stderr, "Usage: %s <file\-to\-exec>\en", argv[0]); - exit(EXIT_FAILURE); - } -\& - newargv[0] = argv[1]; -\& - execve(argv[1], newargv, newenviron); - perror("execve"); /* execve() returns only on error */ - exit(EXIT_FAILURE); -} -.EE -.\" SRC END -.in -.P -We can use the second program to exec the first as follows: -.P -.in +4n -.EX -.RB "$" " cc myecho.c \-o myecho" -.RB "$" " cc execve.c \-o execve" -.RB "$" " ./execve ./myecho" -argv[0]: ./myecho -argv[1]: hello -argv[2]: world -.EE -.in -.P -We can also use these programs to demonstrate the use of a script -interpreter. -To do this we create a script whose "interpreter" is our -.I myecho -program: -.P -.in +4n -.EX -.RB "$" " cat > script" -.B #!./myecho script\-arg -.B \[ha]D -.RB "$" " chmod +x script" -.EE -.in -.P -We can then use our program to exec the script: -.P -.in +4n -.EX -.RB "$" " ./execve ./script" -argv[0]: ./myecho -argv[1]: script\-arg -argv[2]: ./script -argv[3]: hello -argv[4]: world -.EE -.in -.SH SEE ALSO -.BR chmod (2), -.BR execveat (2), -.BR fork (2), -.BR get_robust_list (2), -.BR ptrace (2), -.BR exec (3), -.BR fexecve (3), -.BR getauxval (3), -.BR getopt (3), -.BR system (3), -.BR capabilities (7), -.BR credentials (7), -.BR environ (7), -.BR path_resolution (7), -.BR ld.so (8) |